Appendix

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The Appendix is intended for use in conjunction with the 2022 Annual Air Quality in Ontario Report. The Appendix briefly describes the provincial Air Quality Health Index (AQHI) network, quality assurance and quality control procedures, and the Ministry of the Environment, Conservation and Parks’ air quality database. It also includes a series of tables displaying station locations and a listing of the summary statistics including means, maximums, percentile values and the number of exceedances of the Ontario Ambient Air Quality Criteria (AAQC) for each pollutant. In addition, trends for select common pollutants are displayed for a 10-year period, whereas trends for select research parameters are displayed for a 7-year period.

Monitoring network operations

Network description

In 2022, the ministry operated 38 ambient air monitoring sites across Ontario as part of the AQHI network. The AQHI network was comprised of 131 continuous monitoring instruments at 38 sites. These instruments have the capability of recording minute data (approximately 70 million data points per year) that are used to scan and validate the continuous hourly data.

Quality assurance and quality control

Day-to-day maintenance and support of the instruments are administered by ministry staff. Instrumentation precision is verified by daily automatic internal zero and span checks. Data analysts and station operators review span control charts to confirm instrument precision using a telemetry system. A quarterly quality assurance and quality control (QA/QC) review is performed on the ambient data set to highlight anomalies and administer corrective action in a timely manner.

The air monitoring station operators routinely inspect and maintain monitoring equipment and stations with mandatory quarterly on-site visits where secondary transfer standards are used to calibrate instrumentation. Station maintenance activities are recorded using Fieldworker Inc. software, an electronic documentation solution; this information is transferred directly to the ministry’s database. The instrumentation used throughout the provincial air monitoring network has been standardized to Thermo Electron Corporation analyzers to streamline parts inventory and leverage common hardware used within each analyzer. The following is a summary of the instrumentation deployed within the network and are all US EPA designated equivalent methods:

Nitrogen Oxides – TE42C/I
Fine Particulate Matter – SHARP 5030
Ozone – TE49C/I
Sulphur Dioxide – TE43I
Carbon Monoxide – TE48I
Total Reduced Sulphur – TE43I/CDN101

The ministry operates a laboratory with gas reference standards that adhere to those of the U.S. National Institute of Standards and Technology (NIST) and the Air Quality Research Division of Environment and Climate Change Canada. The secondary transfer standards used by station operators are referenced and certified to the ministry’s NIST primary standards on a quarterly basis.

The TRAP instrumentation used throughout the roadside air monitoring network include:

Ultrafine Particles – Teledyne API Model 651
Black Carbon in PM_2.5 – Magee Scientific AE33 Aethalometer
Heavy Metals in PM_2.5 – Cooper Environmental Xact 625
Major Components in PM_2.5 – Aerodyne Quadrupole Aerosol Chemical Speciation Monitor (ACSM)

The Ontario ambient air quality monitoring network undergoes constant maintenance to ensure a high standard of quality control. Continuous real-time data are consistently reviewed, assessed and validated by ministry staff. Immediate actions are taken to correct any inconsistencies that may affect the validity of the data. These measures ensure ambient air monitoring data are valid, complete, comparable, representative and accurate. As a result, the 2022 ambient air quality monitoring network had 98.3% valid data from over one million hourly data points.

Data base

The ambient air quality data used in this report are stored in the ministry’s air quality information system (AQUIS) and are made available through the Air Quality Ontario web site, and the Ontario Data Catalogue. A statistical pattern test is used to identify data anomalies, such as unusual pollutant concentrations. Each pollutant has a predetermined concentration range based on historical data. Values outside this range are flagged for further investigation.

Data are obtained from automated ambient air monitoring instruments that operate continuously to produce an average measurement for every hour for a possible total of 8,760 measurements in a given year. Hourly parameters measured include NO/NO₂/NOx, PM_2.5, O₃, SO₂, CO and TRS compounds. An annual mean requires at least 6,570 hourly readings. In addition, each quarter of the year should have 75% valid data for PM_2.5, whereas for ozone, only the 2^nd and 3^rd quarters of the year require 75% valid data based on protocols that are consistent with the Canadian Council of Ministers of the Environment (CCME) and the United States Environmental Protection Agency (U.S. EPA). For VOC samples, half of the method detection limit (MDL) is applied as appropriate to concentrations measured below the detection limit. An annual and/or monthly mean for 24-hour VOC samples requires 50% of valid samples. The 50% data requirement also applies to the research parameters (ultrafine particles, black carbon and trace metals and major components of PM_2.5).

Network descriptive table

The AQHI network for 2022 is summarized in the 2022 Ontario Continuous Ambient Air Monitoring Network. The table displays the station name, numerical identifier and pollutants measured. The numerical identifier is the station (ID) number, the first digit of which identifies the geographic region in which the station is located. Air monitoring stations within the AQHI network can measure up to six common pollutants (NO₂, PM_2.5, ozone, SO₂, CO and TRS compounds) based on the pollutant(s) of concern for the regional area it represents.

The 2022 Ontario Continuous Ambient Air Monitoring Network also identifies the type of air monitoring site: ambient, roadside, Canadian Ambient Air Quality Standard (CAAQS), and/or National Air Pollution Surveillance (NAPS). Ambient sites represent the general air quality of an area without any direct influence of local industrial sources. Road-side sites are typically within approximately 100 m of a major roadway with daily traffic volumes greater than 10,000 vehicles per day.

Annual statistics and trends

The annual statistical data and trends for various continuous pollutants and selected volatile organic compounds are presented in the Appendix. The annual averages, maximums and percentiles are displayed in the annual statistics tables. (A percentile is the value equal to or below which a given percentage of the data set falls. For example, if 70% of the data are equal to or below 0.10 ppm, the 70^th percentile is 0.10 ppm).

The trends are calculated from monthly means through the Mann-Kendall (M-K) test. The M-K test is a nonparametric statistical approach that can be applied to data without making assumptions on the nature of the data distribution. The M-K test is essentially a test for uniform progression (zero change) in the slope of the linear regression of time-ordered data versus time (Gilbert, 1987). The M-K test is particularly suitable for environmental monitoring data since missing, trace and below detection limit values can be handled. This test can also be used to compare trends at multiple stations. The seasonal Kendall test, also performed in this Report, is a generalization of the M-K test (Gilbert, 1987) for use to determine the true trend when there are seasonal cycles in the data which do not constitute a true long-term trend. The change over time was based on the Sen’s slope, also known as the Thiel-Sen’s estimator of linear trend. The Sen’s slope is closely related to and applied in conjunction with the M-K Test. Compared to the common least squares regression, the Sen’s slope procedure is a nonparametric method for computing the value of the true slope when there are gross errors or outliers in the data without making assumptions of a normal distribution on the data (Gilbert, 1987).

Other informative tables

Calculated CAAQS metrics for PM_2.5, ozone, NO₂ and SO₂ are presented for 2022 (based on a three-year average, 2020-2022) and over a 10-year period in Canadian Ambient Air Quality Standard Reporting. The air zone management levels associated to each CAAQS reporting pollutant are also provided for reference. The percentage distribution of hourly AQHI readings within the various health risk categories for each of the 38 monitoring sites, and the number of air quality alerts issued in Ontario during 2022 are summarized in AQHI and Air Quality Alert Program Reporting.

2022 air monitoring network

2022 Ontario continuous ambient air monitoring network
ID	Station name	Station location	Year	Latitude	Longtiude	Air intake	Type	AQHI	NO₂	PM_2.5	O₃	SO₂	CO	TRS
12008	Windsor Downtown	467 University Ave. W.	1969	42°18'58.8"	-83°02'37.2"	4	A/RS/C/N	Y	T	T	T	T	T	N/A
12016	Windsor West	College Ave./South St.	1975	42°17'34.4"	-83°04'23.3"	4	A/RS/N	Y	T	T	T	T	N/A	T
13001	Chatham	435 Grand Ave. W.	2005	42°24'13.3"	-82°12'29.9"	15	A/C/N	Y	T	T	T	N/A	N/A	N/A
14111	Sarnia	700 Christina St. N.	2016	42°59'25.0"	-82°23'43.2"	3	A/C/N	Y	T	T	T	T	N/A	T
15020	Grand Bend	Point Blake Conservation Area	1991	43°19'59.1"	-81°44'34.4"	5	A/N	Y	T	T	T	N/A	N/A	N/A
15026	London	42 St. Julien St.	2013	42°58'28.1"	-81°12'03.1"	5	A/C/N	Y	T	T	T	N/A	N/A	N/A
16015	Port Stanley	43665 Dexter Line, Elgin Water T. Plant	2002	42°40'19.5"	-81°09'46.4"	5	A/N	Y	T	T	T	N/A	N/A	N/A
18007	Tiverton	4^th Concession/Bruce Rd. 23	1979	44°18'52.1"	-81°32'59.0"	4	A/N	Y	N/A	T	T	N/A	N/A	N/A
21005	Brantford	324 Grand River Ave.	2004	43°08'19.0"	-80°17'33.5"	5	A/C/N	Y	T	T	T	N/A	N/A	N/A
26060	Kitchener	West Ave./Homewood Ave.	1990	43°26'37.8"	-80°30'13.7"	5	A/C/N	Y	T	T	T	N/A	N/A	N/A
27067	St. Catharines	Argyle Cres., Pump Stn.	1987	43°09'36.2"	-79°14'05.1"	4	A/C/N	Y	T	T	T	N/A	N/A	N/A
28028	Guelph	Exhibition St./Clark St. W.	2000	43°33'05.8"	-80°15'51.0"	4	A/C/N	Y	T	T	T	N/A	N/A	N/A
29000	Hamilton Downtown	Elgin St./Kelly St.	1987	43°15'28.0"	-79°51'42.0"	4	A/RS/C/N	Y	T	T	T	T	T	T
29118	Hamilton West	Main St. W./Hwy 403	1985	43°15'26.8"	-79°54'27.9"	3	A/RS/N	Y	T	T	T	N/A	N/A	N/A
29214	Hamilton Mountain	250 Fennell Ave. W.	2019	43°14'28.4"	-79°53'21.9"	3	A/C/N	Y	T	T	T	T	N/A	N/A
31129	Toronto Downtown	55 John St., Metro Hall	2019	43°38'43.5"	-79°23'20.7"	2	A/RS/C/N	Y	T	T	T	N/A	N/A	N/A
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	1970	43°44'52.5"	-79°16'26.6"	4	A/RS/C/N	Y	T	T	T	N/A	N/A	N/A
34021	Toronto North	4905 Dufferin St., ECCC	1988	43°46'53.8"	-79°25'03.8"	5	A/RS/C/N	Y	T	T	T	T	T	N/A
35125	Toronto West	125 Resources Rd.	2003	43°42'34.0"	-79°32'36.6"	8	A/RS/C/N	Y	T	T	T	T	T	N/A
44008	Burlington	North Shore Blvd. E./Lakeshore Rd.	1979	43°18'54.4"	-79°48'09.5"	5	A/C/N	Y	T	T	T	N/A	N/A	N/A
44017	Oakville	EightLine/Glenashton Dr., Halton Reservoir	2003	43°29'12.9"	-79°42'08.2"	12	A/C/N	Y	T	T	T	N/A	N/A	N/A
44029	Milton	1120 Main St. E.	2019	43°31'46.7"	-79°51'44.8"	4	A/C/N	Y	T	T	T	T	N/A	N/A
45027	Oshawa	Brittania Ave. W., Ep Taylor Stables	2005	43°57'07.5"	-78°54'45.2"	7	A/C/N	Y	T	T	T	N/A	N/A	N/A
46090	Brampton	109 Mclaughlin Rd. S.	2000	43°41'55.5"	-79°46'51.3"	5	A/C/N	Y	T	T	T	N/A	N/A	N/A
46108	Mississauga	3359 Mississauga Rd. N., U of T Campus	2007	43°32'49.1"	-79°39'31.3"	5	A/C/N	Y	T	T	T	N/A	N/A	N/A
47045	Barrie	83 Perry St.	2001	44°22'56.5"	-79°42'08.3"	5	A/C/N	Y	T	T	T	N/A	N/A	N/A
48006	Newmarket	Eagle St. W./Mccaffrey Rd.	2001	44°02'39.5"	-79°28'59.7"	5	A/N	Y	T	T	T	N/A	N/A	N/A
49005	Parry Sound	7 Bay St.	2001	45°20'16.3"	-80°02'17.4"	5	A/N	Y	T	T	T	N/A	N/A	N/A
49010	Dorset	1026 Bellwood Acres Rd.	1981	45°13'27.4"	-78°55'58.6"	3	A/N	Y	N/A	T	T	N/A	N/A	N/A
51001	Ottawa Downtown	Rideau St./Wurtemburg St.	1971	45°26'03.6"	-75°40'33.6"	4	A/C/N	Y	T	T	T	T	N/A	N/A
52023	Kingston	23 Beechgrove Lane	2014	44°13'11.5"	-76°31'16.1"	5	A/C/N	Y	T	T	T	N/A	N/A	N/A
54012	Belleville	2 Sidney St., Water Treatment Plant	2002	44°09'01.9"	-77°23'43.8"	10	A/N	Y	T	T	T	N/A	N/A	N/A
56051	Cornwall	Bedford St./3rd St. W.	1970	45°01'04.7"	-74°44'06.8"	4	A/N	Y	T	T	T	N/A	N/A	N/A
59006	Peterborough	10 Hospital Dr.	1998	44°18'06.9"	-78°20'46.4"	10	A/C/N	Y	T	T	T	N/A	N/A	N/A
63203	Thunder Bay	421 James St. S.	2004	48°22'45.8"	-89°17'24.6"	15	A/RS/C/N	Y	T	T	T	N/A	N/A	N/A
71078	Sault Ste. Marie	Sault College	2004	46°31'59.5"	-84°18'35.7"	8	A/C/N	Y	T	T	T	T	N/A	T
75010	North Bay	Chippewa St. W., Dept. National Defence	1979	46°19'23.5"	-79°26'57.4"	4	A/RS/N	Y	T	T	T	N/A	N/A	N/A
77233	Sudbury	155 Elm St.	2013	46°29'31.0"	-81°00'11.2"	3	A/C/N	Y	T	T	T	T	N/A	N/A
Total								38	36	38	38	11	4	4

Notes:

ID: station identfication number
Year: year station began monitoring
Air intake: height of air intake above ground (m)
Type: type of monitoring site
A: ambient
RS: road-side
C: Canadian Ambient Air Quality Standard (CAAQS)
N: National Air Pollution Surveillance (NAPS)
AQHI: Air Quality Health Index
T: telemetry
NO₂: nitrogen dioxide
PM_2.5: fine particulate matter
O₃: ground-level ozone
SO₂: sulphur dioxide
CO: carbon monoxide
TRS: total reduced sulphur
Y: yes

2022 annual statistics

2022 nitric oxide (NO) annual statistics

Unit: parts per billion (ppb)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Max 1h	Max 24h
12008	Windsor Downtown	467 University Ave. W.	8689	0.2	0.6	1.00	1.7	4.2	29.3	2.4	188.8	30.4
12016	Windsor West	College Ave./South St.	8645	0.2	0.3	0.60	1.2	3.6	47.1	2.4	183.8	31.9
13001	Chatham	435 Grand Ave. W.	8597	0.1	0.3	0.50	0.9	2.4	10.3	1.1	52.9	9.5
14111	Sarnia	700 Christina St. N.	8613	0.7	1.0	1.30	1.6	3.0	13.9	2.0	107.2	16.7
15020	Grand Bend	Point Blake Conservation Area	8553	0.0	0.0	0.10	0.1	0.5	1.8	0.2	9.0	1.5
15026	London	42 St. Julien St.	8660	0.0	0.1	0.20	0.5	1.4	13.2	0.8	82.2	11.0
16015	Port Stanley	43665 Dexter Line, Elgin Water T. Plt	8681	0.0	0.0	0.10	0.2	0.7	2.4	0.3	15.7	2.0
21005	Brantford	324 Grand River Ave.	8594	0.0	0.1	0.20	0.4	1.3	8.2	0.7	52.5	7.0
26060	Kitchener	West Ave./Homewood Ave.	8556	0.1	0.2	0.30	0.5	1.6	19.2	1.1	93.9	38.5
27067	St. Catharines	Argyle Cres., Pump Stn.	8697	0.2	0.4	0.50	0.8	1.9	17.5	1.3	90.9	18.5
28028	Guelph	Exhibition St./Clark St. W.	8688	0.0	0.1	0.20	0.5	1.5	17.2	0.9	64.7	17.9
29000	Hamilton Downtown	Elgin St./Kelly St.	8610	0.0	0.2	0.90	2.0	7.7	51.7	3.5	126.9	47.1
29118	Hamilton West	Main St. W./Hwy 403	8658	0.3	0.4	0.90	1.8	7.7	51.2	3.6	105.6	35.2
29214	Hamilton Mountain	250 Fennell Ave. W.	8695	0.6	1.0	1.40	2.4	6.1	28.9	3.0	84.2	31.9
31129	Toronto Downtown	55 John St.	8583	1.0	2.0	3.40	6.4	16.3	54.3	7.1	254.1	38.0
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	8681	0.0	0.4	1.00	2.1	5.3	27.7	2.5	144.2	27.4
34021	Toronto North	4905 Dufferin St., ECCC	8727	0.0	0.2	0.70	1.6	4.8	30.3	2.3	137.2	29.8
35125	Toronto West	125 Resources Rd.	8604	0.1	0.6	1.90	4.7	14.1	62.8	5.9	136.6	47.2
44008	Burlington	North Shore Blvd. E./Lakeshore Rd.	8693	0.5	0.8	1.40	2.4	5.8	30.9	3.1	159.4	23.3
44017	Oakville	EightLine/Glenashton Dr., Halton Res.	8641	0.2	0.4	0.50	1.0	3.5	20.9	1.7	68.9	16.8
44029	Milton	1120 Main St. E.	8691	0.4	0.6	0.90	1.7	4.9	47.1	3.1	139.1	38.6
45027	Oshawa	Brittania Ave. W., EP Taylor Stables	8654	0.0	0.0	0.40	0.7	1.4	5.8	0.7	21.5	5.5
46090	Brampton	109 McLaughlin Rd. S.	8693	0.0	0.2	0.30	0.7	3.5	31.4	1.9	137.2	28.1
46108	Mississauga	3359 Mississauga Rd. N., U of T Campus	8640	0.1	0.2	0.40	0.9	4.1	34.4	2.2	103.5	42.5
47045	Barrie	83 Perry St.	8547	0.2	0.5	0.70	1.0	2.5	22.2	1.6	104.1	21.8
48006	Newmarket	Eagle St. W./McCaffrey Rd.	8623	0.1	0.3	0.50	0.7	2.1	13.1	1.1	69.4	9.7
49005	Parry Sound	7 Bay St.	8628	0.1	0.2	0.40	0.5	0.9	5.1	0.6	28.6	3.7
51001	Ottawa Downtown	Rideau St./Wurtemburg St.	8658	0.4	0.6	0.80	1.1	2.5	13.7	1.5	64.3	12.6
52023	Kingston	23 Beechgrove Lane	8687	0.2	0.3	0.40	0.6	1.2	4.7	0.6	26.9	4.9
54012	Belleville	2 Sidney St., Water Treatment Plant	8693	0.1	0.1	0.20	0.6	2.9	16.5	1.2	73.0	9.4
56051	Cornwall	Bedford St./3rd St. W.	8690	0.0	0.2	0.30	0.6	1.9	33.3	1.6	142.9	36.6
59006	Peterborough	10 Hospital Dr.	8602	0.0	0.1	0.30	0.7	1.8	11.0	0.9	53.9	13.5
63203	Thunder Bay	421 James St. S.	8718	0.7	1.0	1.50	2.7	10.0	36.8	4.1	86.7	25.2
71078	Sault Ste. Marie	Sault College	8745	0.2	0.4	0.70	1.2	2.9	12.0	1.4	54.4	7.3
75010	North Bay	Chippewa St. W., Dept. National Defence	8709	0.5	0.6	0.80	1.2	2.7	15.4	1.5	71.8	13.8
77233	Sudbury	155 Elm St.	8683	0.5	0.7	1.10	1.7	4.3	36.5	2.7	112.3	34.5

2022 nitrogen dioxide (NO₂) annual statistics

Unit: parts per billion (ppb)
NO₂ 1h AAQC: 200 ppb
NO₂ 24h AAQC: 100 ppb

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Max 1h	Max 24h
12008	Windsor Downtown	467 University Ave. W.	8689	3.4	5.2	7.3	10.2	17.7	38.5	9.4	60.3	28.3
12016	Windsor West	College Ave./South St.	8645	2.4	4.0	5.9	8.7	16.3	36.0	8.0	51.5	26.1
13001	Chatham	435 Grand Ave. W.	8597	1.3	2.4	3.5	5.1	8.8	19.2	4.5	44.2	18.4
14111	Sarnia	700 Christina St. N.	8613	1.3	2.7	4.7	7.9	14.6	28.9	6.7	49.6	25.5
15020	Grand Bend	Point Blake Conservation Area	8553	0.7	1.4	2.2	3.3	5.2	9.2	2.7	22.1	8.6
15026	London	42 St. Julien St.	8660	1.3	2.6	3.9	5.6	9.5	22.4	5.0	43.2	21.9
16015	Port Stanley	43665 Dexter Line, Elgin Water T. Plt	8681	0.6	1.2	1.8	2.6	4.2	7.9	2.2	18.7	7.0
21005	Brantford	324 Grand River Ave.	8594	1.9	2.7	3.7	5.2	9.7	20.5	5.0	35.5	18.1
26060	Kitchener	West Ave./Homewood Ave.	8556	1.3	2.4	3.7	5.8	11.2	28.0	5.4	46.4	24.1
27067	St. Catharines	Argyle Cres., Pump Stn.	8697	1.9	2.9	4.0	6.0	11.9	25.5	5.7	47.1	20.0
28028	Guelph	Exhibition St./Clark St. W.	8688	0.9	2.0	3.4	5.6	11.1	26.9	5.1	44.1	23.4
29000	Hamilton Downtown	Elgin St./Kelly St.	8610	3.2	5.0	7.5	12.0	23.2	39.9	10.6	57.0	35.7
29118	Hamilton West	Main St. W./Hwy 403	8658	2.9	4.5	6.8	11.3	21.7	36.3	9.8	54.6	31.1
29214	Hamilton Mountain	250 Fennell Ave. W.	8695	1.7	2.6	4.0	6.6	13.7	26.4	6.1	43.7	24.0
31129	Toronto Downtown	55 John St.	8583	6.2	9.2	12.2	16.3	25.9	43.8	14.4	75.6	35.1
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	8681	3.1	5.2	7.5	11.0	20.3	38.6	9.9	63.7	32.6
34021	Toronto North	4905 Dufferin St., ECCC	8727	2.9	5.0	7.7	12.0	20.9	39.8	10.2	59.0	32.2
35125	Toronto West	125 Resources Rd.	8604	4.2	7.5	10.8	15.8	26.0	41.1	13.2	57.8	33.3
44008	Burlington	North Shore Blvd. E./Lakeshore Rd.	8693	2.3	4.1	6.3	9.7	17.5	35.3	8.5	52.2	26.7
44017	Oakville	EightLine/Glenashton Dr., Halton Res.	8641	2.0	3.4	5.4	8.6	17.2	34.1	7.8	45.8	29.0
44029	Milton	1120 Main St. E.	8691	1.6	3.5	5.6	9.1	19.3	35.7	8.3	55.6	28.3
45027	Oshawa	Brittania Ave. W., EP Taylor Stables	8654	0.8	1.6	2.6	4.2	8.1	16.4	3.7	32.5	16.2
46090	Brampton	109 McLaughlin Rd. S.	8693	1.0	2.4	4.3	7.8	18.1	35.2	7.2	54.5	28.5
46108	Mississauga	3359 Mississauga Rd. N., U of T Campus	8640	1.6	3.2	5.2	8.7	16.7	32.6	7.5	45.7	29.4
47045	Barrie	83 Perry St.	8547	1.6	2.5	3.7	6.0	12.8	30.4	5.8	49.6	26.2
48006	Newmarket	Eagle St. W./McCaffrey Rd.	8623	0.9	1.9	3.4	6.1	13.0	31.8	5.6	49.8	23.6
49005	Parry Sound	7 Bay St.	8628	0.5	0.9	1.5	2.4	5.1	15.3	2.4	36.2	13.6
51001	Ottawa Downtown	Rideau St./Wurtemburg St.	8658	1.4	2.6	4.0	6.5	13.4	30.9	6.1	48.2	23.0
52023	Kingston	23 Beechgrove Lane	8687	1.0	1.5	2.3	3.4	7.1	21.7	3.5	42.2	19.0
54012	Belleville	2 Sidney St., Water Treatment Plant	8693	1.0	1.7	2.6	4.1	9.0	25.0	4.2	39.8	21.0
56051	Cornwall	Bedford St./3rd St. W.	8690	1.2	1.9	2.9	4.6	11.9	30.3	5.1	56.3	25.4
59006	Peterborough	10 Hospital Dr.	8602	0.9	1.8	3.0	4.9	9.2	27.6	4.5	45.5	27.5
63203	Thunder Bay	421 James St. S.	8718	1.3	2.6	4.3	7.3	16.5	36.9	7.0	55.6	35.4
71078	Sault Ste. Marie	Sault College	8745	1.1	1.8	2.6	4.0	7.9	18.7	3.8	41.4	13.9
75010	North Bay	Chippewa St. W., Dept. National Defence	8709	0.8	1.4	2.2	3.9	9.4	27.9	4.1	40.7	20.5
77233	Sudbury	155 Elm St.	8683	1.3	2.2	3.6	6.0	13.8	41.0	6.1	50.8	29.1

2022 nitrogen oxides (NO_x) annual statistics

Unit: parts per billion (ppb)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Max 1h	Max 24h
12008	Windsor Downtown	467 University Ave. W.	8689	4.0	6.1	8.6	12.0	21.1	64.8	11.8	249.1	54.5
12016	Windsor West	College Ave./South St.	8645	2.8	4.6	6.7	10.0	19.2	77.2	10.4	227.8	57.8
13001	Chatham	435 Grand Ave. W.	8597	1.6	2.9	4.2	6.2	10.9	25.8	5.6	96.1	27.6
14111	Sarnia	700 Christina St. N.	8613	2.4	3.9	6.0	9.4	17.5	40.9	8.6	138.1	41.5
15020	Grand Bend	Point Blake Conservation Area	8553	0.7	1.5	2.4	3.4	5.6	10.2	2.9	23.5	9.3
15026	London	42 St. Julien St.	8660	1.5	2.9	4.2	6.1	10.7	29.5	5.8	113.1	28.5
16015	Port Stanley	43665 Dexter Line, Elgin Water T. Plt	8681	0.7	1.3	1.9	2.8	4.8	9.6	2.4	23.4	7.6
21005	Brantford	324 Grand River Ave.	8594	2.1	3.0	3.9	5.6	11.1	26.3	5.6	86.2	23.5
26060	Kitchener	West Ave./Homewood Ave.	8556	1.6	2.7	4.1	6.4	12.3	42.7	6.5	137.3	58.5
27067	St. Catharines	Argyle Cres., Pump Stn.	8697	2.3	3.3	4.6	6.8	13.8	40.1	7.0	106.5	35.0
28028	Guelph	Exhibition St./Clark St. W.	8688	1.0	2.3	3.8	6.1	12.7	40.5	6.0	104.0	39.6
29000	Hamilton Downtown	Elgin St./Kelly St.	8610	3.2	5.6	8.6	14.3	29.8	83.98	14.0	159.7	77.5
29118	Hamilton West	Main St. W./Hwy 403	8658	3.4	5.2	7.8	13.5	29.5	80.24	13.4	142.5	58.8
29214	Hamilton Mountain	250 Fennell Ave. W.	8695	2.5	3.7	5.5	9	19.7	53.21	9.1	108.2	55.9
31129	Toronto Downtown	55 John St.	8583	7.8	11.8	16.3	23.2	40.0	91.3	21.5	311.7	70.0
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	8681	3.5	6.2	8.8	13	24.8	64.06	12.5	207.9	53.1
34021	Toronto North	4905 Dufferin St., ECCC	8727	3.3	5.8	8.9	13.5	25.2	65.25	12.5	194.5	57.9
35125	Toronto West	125 Resources Rd.	8604	5	8.9	13.4	20.6	38.7	95.39	19.1	183.1	79.3
44008	Burlington	North Shore Blvd. E./Lakeshore Rd.	8693	3.1	5.3	8	12.2	22.7	62.52	11.5	196.1	48.1
44017	Oakville	EightLine/Glenashton Dr., Halton Res.	8641	2.4	3.9	6.1	9.8	20.5	51.52	9.5	104.2	44.8
44029	Milton	1120 Main St. E.	8691	2.4	4.4	6.8	10.7	24.2	78.76	11.3	194.7	66.9
45027	Oshawa	Brittania Ave. W., EP Taylor Stables	8654	1	1.9	3	4.8	9.4	20.8	4.3	46.7	20.8
46090	Brampton	109 McLaughlin Rd. S.	8693	1.3	2.7	4.8	8.8	21.5	62.22	9.1	189.7	56.5
46108	Mississauga	3359 Mississauga Rd. N., U of T Campus	8640	1.9	3.6	5.8	9.7	21.1	62.9	9.7	145.7	70.6
47045	Barrie	83 Perry St.	8547	2.1	3.2	4.5	6.9	15.4	48.46	7.4	151.6	42.5
48006	Newmarket	Eagle St. W./McCaffrey Rd.	8623	1.2	2.4	4	6.9	15.1	40.88	6.7	104.7	30.7
49005	Parry Sound	7 Bay St.	8628	0.8	1.3	1.9	2.9	6.1	18.6	3.0	52.1	17.3
51001	Ottawa Downtown	Rideau St./Wurtemburg St.	8658	2.1	3.4	4.9	7.7	15.9	39.74	7.5	103.4	33.4
52023	Kingston	23 Beechgrove Lane	8687	1.3	1.9	2.7	4	8.1	25.66	4.1	65.7	23.8
54012	Belleville	2 Sidney St., Water Treatment Plant	8693	1.2	2	3	5	12.1	36.91	5.4	104.8	29.3
56051	Cornwall	Bedford St./3rd St. W.	8690	1.4	2.2	3.3	5.3	13.9	59.98	6.7	199.2	55.8
59006	Peterborough	10 Hospital Dr.	8602	1.1	2.1	3.4	5.5	10.6	37.9	5.4	89.6	37.1
63203	Thunder Bay	421 James St. S.	8718	2.3	3.8	6.1	10.5	26.2	67.22	11.1	134.7	60.5
71078	Sault Ste. Marie	Sault College	8745	1.5	2.3	3.4	5.4	11.0	27.5	5.2	88.3	21.2
75010	North Bay	Chippewa St. W., Dept. National Defence	8709	1.3	2.1	3.2	5.2	12.2	40.7	5.7	106.2	33.2
77233	Sudbury	155 Elm St.	8683	1.9	3.2	4.8	7.7	17.9	73.38	8.8	157.2	60.7

2022 fine particulate matter (PM_2.5) annual statistics

Unit: micrograms per cubic metre (μg/m³)
PM_2.5 24h Reference Level: 27 μg/m³
PM_2.5 Annual Reference Level: 8.8 μg/m³

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Max 1h	Max 24h	Number of times above 24h reference level	Number of times above annual reference level
12008	Windsor Downtown	467 University Ave. W.	8743	2	4	6	9	15	28	7.83	55	26.2	0	0
12016	Windsor West	College Ave./South St.	8705	3	5	8	10	16	29	8.82	47	31.1	1	1
13001	Chatham	435 Grand Ave. W.	8424	2	3	5	8	14	27	6.74	67	24.8	0	0
14111	Sarnia	700 Christina St. N.	8665	1	3	5	9	16	27	7.09	55	26.7	0	0
15020	Grand Bend	Point Blake Conservation Area	8258	1	3	4	7	11	24	5.63	39	22.1	0	0
15026	London	42 St. Julien St.	8622	2	4	6	8	13	25	7.07	55	28.8	1	0
16015	Port Stanley	43665 Dexter Line, Elgin Water T. Plt	8709	2	3	5	8	14	26	6.74	60	26.5	0	0
18007	Tiverton	4^th Concession/Bruce Rd. 23	8556	1	2	3	5	10	20	4.60	47	27.5	1	0
21005	Brantford	324 Grand River Ave.	8647	2	4	6	8	13	26	6.97	48	22.5	0	0
26060	Kitchener	West Ave./Homewood Ave.	8579	1	3	6	9	16	29	7.48	69	30.5	1	0
27067	St. Catharines	Argyle Cres., Pump Stn.	8695	1	3	4	6	11	22	5.41	32	21.8	0	0
28028	Guelph	Exhibition St./Clark St. W.	8487	2	4	6	8	13	24	6.74	38	25.7	0	0
29000	Hamilton Downtown	Elgin St./Kelly St.	8645	2	4	7	11	18	33	8.64	90	34.8	3	0
29118	Hamilton West	Main St. W./Hwy 403	8715	2	4	6	9	14	26	7.30	83	29.9	1	0
29214	Hamilton Mountain	250 Fennell Ave. W.	8567	2	4	6	9	16	30	7.71	88	35.3	2	0
31129	Toronto Downtown	55 John St.	8729	2	5	7	9	15	29	7.92	50	30.6	2	0
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	8686	1	4	6	8	13	26	6.70	83	30.0	1	0
34021	Toronto North	4905 Dufferin St., ECCC	8656	2	4	6	8	13	26	6.79	50	33.0	1	0
35125	Toronto West	125 Resources Rd.	8670	2	4	6	8	13	24	6.90	58	28.4	1	0
44008	Burlington	North Shore Blvd. E./Lakeshore Rd.	8572	2	4	5	8	13	24	6.62	39	26.6	0	0
44017	Oakville	EightLine/Glenashton Dr., Halton Res.	8624	2	4	6	8	13	25	6.74	50	24.8	0	0
44029	Milton	1120 Main St. E.	8684	2	4	6	8	13	26	6.87	50	27.6	1	0
45027	Oshawa	Brittania Ave. W., EP Taylor Stables	8671	2	3	5	6	11	21	5.71	41	24.7	0	0
46090	Brampton	109 McLaughlin Rd. S.	8696	2	4	6	8	13	25	7.11	523	72.9	2	0
46108	Mississauga	3359 Mississauga Rd. N., U of T Campus	8682	2	3	6	9	14	27	7.14	106	35.8	3	0
47045	Barrie	83 Perry St.	8399	2	3	5	7	13	24	6.36	43	24.0	0	0
48006	Newmarket	Eagle St. W./McCaffrey Rd.	8734	1	3	5	8	12	22	6.18	56	21.5	0	0
49005	Parry Sound	7 Bay St.	8668	1	2	4	6	10	18	4.67	33	17.4	0	0
49010	Dorset	1026 Bellwood Acres Rd.	8682	1	2	3	5	9	17	4.47	28	16.4	0	0
51001	Ottawa Downtown	Rideau St./Wurtemburg St.	8752	2	3	5	7	11	20	5.91	40	24.0	0	0
52023	Kingston	23 Beechgrove Lane	8718	1	3	4	7	10	18	5.29	41	17.6	0	0
54012	Belleville	2 Sidney St., Water Treatment Plant	8741	2	3	4	6	11	19	5.49	50	19.9	0	0
56051	Cornwall	Bedford St./3rd St. W.	8726	2	3	5	8	13	25	6.40	49	28.1	1	0
59006	Peterborough	10 Hospital Dr.	8601	1	3	5	8	14	26	6.64	45	27.1	1	0
63203	Thunder Bay	421 James St. S.	8748	2	3	4	6	9	15	5.03	30	17.5	0	0
71078	Sault Ste. Marie	Sault College	8727	1	2	3	5	9	18	4.45	51	16.3	0	0
75010	North Bay	Chippewa St. W., Dept. National Defence	8691	2	3	4	6	10	18	5.06	34	15.8	0	0
77233	Sudbury	155 Elm St.	8707	1	3	4	6	11	21	5.23	45	19.0	0	0

Notes

Ontario uses the 24-hour PM_2.5 CAAQS “as is” for comparison to the 24-hour measurement of air quality data; this value is considered a Reference Level.
Ontario uses the annual PM_2.5 CAAQS “as is” for comparison to a single annual average of air quality data; this value is considered a Reference Level.

2022 ground-level ozone (O₃) annual statistics

Unit: parts per billion (ppb)
O₃ 1h AAQC: 80 ppb

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Max 1h	Max 24h	Number of times above 1h criterion
12008	Windsor Downtown	467 University Ave. W.	8529	14	23	30	36	47	65	30.4	84	58.2	4
12016	Windsor West	College Ave./South St.	8682	13	23	29	36	47	63	29.5	81	56.8	1
13001	Chatham	435 Grand Ave. W.	8671	17	25	31	37	46	63	31.6	85	57.9	3
14111	Sarnia	700 Christina St. N.	8613	16	25	31	37	45	62	31.0	97	54.6	5
15020	Grand Bend	Point Blake Conservation Area	8656	18	27	32	37	44	62	31.9	92	60.9	7
15026	London	42 St. Julien St.	8668	12	24	30	36	45	59	29.6	89	60.1	4
16015	Port Stanley	43665 Dexter Line, Elgin Water T. Plt	8678	17	26	31	36	44	60	31.1	89	60.9	6
18007	Tiverton	4^th Concession/Bruce Rd. 23	8616	19	26	32	37	45	61	31.9	85	63.1	6
21005	Brantford	324 Grand River Ave.	8596	11	22	30	36	45	60	29.0	90	60.4	6
26060	Kitchener	West Ave./Homewood Ave.	8558	14	24	29	34.9	43	58	28.9	79	55.5	0
27067	St. Catharines	Argyle Cres., Pump Stn.	8649	14	24	30	36	44	59	29.8	84	59.0	1
28028	Guelph	Exhibition St./Clark St. W.	8672	14	25	31	37	46	63	30.9	82	58.1	2
29000	Hamilton Downtown	Elgin St./Kelly St.	8626	9	20	26	32	41	56	25.9	84	57.1	3
29118	Hamilton West	Main St. W./Hwy 403	8666	6	19	26	32	41	56	25.2	82	61.6	2
29214	Hamilton Mountain	250 Fennell Ave. W.	8677	14	23	28	33	42	57	28.2	81	57.9	1
31129	Toronto Downtown	55 John St.	8581	10	18	24	30	38	54	24.3	72	47.4	0
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	8673	10	20	25	31	39	53	25.1	77	49.0	0
34021	Toronto North	4905 Dufferin St., ECCC	8726	8	18	25	30	40	58	24.3	81	47.6	2
35125	Toronto West	125 Resources Rd.	8606	5	15	22	28	38	55	22.0	70	45.0	0
44008	Burlington	North Shore Blvd. E./Lakeshore Rd.	8692	10	21	27	33	41	56	26.6	79	54.8	0
44017	Oakville	EightLine/Glenashton Dr., Halton Res.	8680	13	22	28	34	43	58	28.1	83	56.8	3
44029	Milton	1120 Main St. E.	8634	9	21	28	34	44	60	27.6	81	57.8	1
45027	Oshawa	Brittania Ave. W., EP Taylor Stables	8718	9.7	21	28	33	40	53	26.6	80	46.1	0
46090	Brampton	109 McLaughlin Rd. S.	8693	10	21	28	33	42	58	27.0	75	52.2	0
46108	Mississauga	3359 Mississauga Rd. N., U of T Campus	8626	7	20	26	32	41	57	25.7	80	55.0	0
47045	Barrie	83 Perry St.	8513	11	20	26	31	39	52	25.3	71	43.7	0
48006	Newmarket	Eagle St. W./McCaffrey Rd.	8693	13	23	28	34	42	58	28.1	90	51.3	2
49005	Parry Sound	7 Bay St.	8480	16	24	30	35	44	57	29.9	73	52.5	0
49010	Dorset	1026 Bellwood Acres Rd.	8693	9	21	27	33	41	54	26.3	64	44.2	0
51001	Ottawa Downtown	Rideau St./Wurtemburg St.	8755	12	21	26	32	40	52	26.1	61	48.9	0
52023	Kingston	23 Beechgrove Lane	8687	17	25	30	35	42	56	29.9	79	57.1	0
54012	Belleville	2 Sidney St., Water Treatment Plant	8693	15	25	31	36	44	59	30.3	96	62.1	7
56051	Cornwall	Bedford St./3rd St. W.	8690	11	21	27	32	40	51	26.3	66	53.3	0
59006	Peterborough	10 Hospital Dr.	8603	13	22	28	33	41	54	27.4	79	51.9	0
63203	Thunder Bay	421 James St. S.	8347	8	19	26	31	38	45	24.6	58	45.0	0
71078	Sault Ste. Marie	Sault College	8745	15	24	29	34	42	55	28.8	75	57.4	0
75010	North Bay	Chippewa St. W., Dept. National Defence	8745	10	21	28	33	43	57	27.2	72	49.7	0
77233	Sudbury	155 Elm St.	8690	12	21	26	30	38	53	25.6	64	49.3	0

2022 sulphur dioxide (SO₂) annual statistics

Unit: parts per billion (ppb)
SO₂ 10 min AAQC: 67 ppb
SO₂ 1h AAQC: 40 ppb
SO₂ 1y AAQC: 4 ppb

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Max 10 min	Max 1h	Max 24h	Number of times above 10 min criteria	Number of times above 1h criteria
12008	Windsor Downtown	467 University Ave. W.	8471	0.0	0.0	0.1	0.3	1.1	5.5	0.45	30.4	24.8	4.7	0	0
12016	Windsor West	College Ave./South St.	8696	0.0	0.1	0.2	0.4	1.5	7.7	0.65	41.7	32.4	6.4	0	0
14111	Sarnia	700 Christina St. N.	8616	0.1	0.2	0.3	0.7	4.6	43.0	2.47	143.4	126.1	59.4	149	101
29000	Hamilton Downtown	Elgin St./Kelly St.	8571	0.0	0.2	0.5	1.3	10.5	49.8	3.73	149.4	99.2	36.5	221	164
29214	Hamilton Mountain	250 Fennell Ave. W.	8648	0.1	0.3	0.5	1.3	8.6	37.7	3.10	145.7	95.5	32.5	62	69
34021	Toronto North	4905 Dufferin St., ECCC	8731	0.0	0.0	0.0	0.1	0.4	2.2	0.17	13.4	7.3	1.7	0	0
35125	Toronto West	125 Resources Rd.	8509	0.0	0.1	0.2	0.3	0.6	2.5	0.29	10.2	8.7	2.1	0	0
44029	Milton	1120 Main St. E.	8421	0.1	0.2	0.3	0.5	1.4	4.9	0.63	38.3	16.1	3.5	0	0
51001	Ottawa Downtown	Rideau St./Wurtemburg St.	8729	0.1	0.1	0.3	0.4	0.5	0.9	0.28	4.5	3.9	1.0	0	0
71078	Sault Ste. Marie	Sault College	8742	0.4	0.4	0.5	0.6	0.9	8.4	0.81	73.9	33.0	6.0	1	0
77233	Sudbury	155 Elm St.	8691	0.0	0.1	0.2	0.4	2.4	15.2	1.09	132.0	46.1	10.3	12	8

2022 carbon monoxide (CO) annual statistics

Unit: parts per million (ppm)
CO 1h AAQC: 30 ppm
CO 8h AAQC: 13 ppm

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Max 1h	Max 8h
12008	Windsor Downtown	467 University Ave. W.	7972	0.15	0.18	0.20	0.23	0.30	0.57	0.22	1.43	0.94
29000	Hamilton Downtown	Elgin St./Kelly St.	7217	0.13	0.16	0.19	0.23	0.40	0.74	0.23	1.79	0.95
34021	Toronto North	4905 Dufferin St., ECCC	8540	0.15	0.17	0.20	0.23	0.29	0.52	0.21	1.42	0.62
35125	Toronto West	125 Resources Rd.	8588	0.16	0.19	0.22	0.26	0.35	0.64	0.24	1.39	0.86

2022 total reduced sulphur (TRS) compounds annual statistics

Unit: parts per billion (ppb)

ID	City	Location	Valid h	90%	99%	Mean	Max 1h	Max 24h
12016	Windsor West	College Ave./South St.	8694	0	3	0.14	15	2.8
14111	Sarnia	700 Christina St. N.	8614	0	1	0.03	2	0.5
29000	Hamilton Downtown	Elgin St./Kelly St.	7328	1	3	0.22	13	2.5
71078	Sault Ste. Marie	Sault College	8610	0	1	0.09	4	1.0

2022 benzene annual statistics

Unit: micrograms per cubic metre (μg/m³)
Benzene 24h AAQC: 2.3 μg/m³
Benzene Annual AAQC: 0.45 μg/m³

ID	City	Number of samples	10%	25%	50%	75%	90%	Max	Min	Mean	Standard deviation	Number of times above 24h criteria	Number of times above annual criteria
12016	Windsor West	51	0.216	0.257	0.340	0.466	0.546	0.788	0.174	0.369	0.139	0	0
14111	Sarnia	59	0.157	0.206	0.370	0.472	0.792	1.990	0.088	0.427	0.329	0	0
15026	London	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
26060	Kitchener	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
29000	Hamilton Downtown	43	0.138	0.267	0.452	0.883	1.688	2.928	0.090	0.706	0.720	2	1
48006	Newmarket	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

2022 toluene annual statistics

Unit: micrograms per cubic metre (μg/m³)
Toluene 24h AAQC (based on odour): 2,000 μg/m

ID	City	Number of samples	10%	25%	50%	75%	90%	Max	Min	Mean	Standard deviation	Number of times above 24h criteria
12016	Windsor West	51	0.212	0.351	0.526	0.846	1.508	3.270	0.100	0.730	0.599	0
14111	Sarnia	59	0.100	0.282	0.554	1.045	1.650	10.088	0.100	0.895	1.401	0
15026	London	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
26060	Kitchener	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
29000	Hamilton Downtown	43	0.280	0.412	0.550	1.107	1.606	4.370	0.100	0.872	0.817	0
48006	Newmarket	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

2022 ethylbenzene annual statistics

Unit: micrograms per cubic metre (μg/m³)
Ethylbenzene 24h AAQC: 1,000 μg/m³

ID	City	Number of samples	10%	25%	50%	75%	90%	Max	Min	Mean	Standard deviation	Number of times above 24h criteria
12016	Windsor West	51	0.035	0.071	0.110	0.161	0.244	0.364	0.035	0.126	0.085	0
14111	Sarnia	59	0.035	0.035	0.084	0.176	0.279	0.492	0.035	0.127	0.116	0
15026	London	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
26060	Kitchener	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
29000	Hamilton Downtown	43	0.035	0.035	0.096	0.144	0.232	0.728	0.035	0.122	0.120	0
48006	Newmarket	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

2022 m- and p-xylene annual statistics

Unit: micrograms per cubic metre (μg/m³)

ID	City	Number of samples	10%	25%	50%	75%	90%	Max	Min	Mean	Standard deviation
12016	Windsor West	51	0.100	0.100	0.296	0.457	0.714	1.158	0.100	0.359	0.273
14111	Sarnia	59	0.100	0.100	0.100	0.320	0.524	1.518	0.100	0.272	0.290
15026	London	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
26060	Kitchener	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
29000	Hamilton Downtown	43	0.100	0.100	0.306	0.424	0.774	2.508	0.100	0.383	0.421
48006	Newmarket	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

2022 o-xylene annual statistics

Unit: micrograms per cubic metre (μg/m³)

ID	City	Number of samples	10%	25%	50%	75%	90%	Max	Min	Mean	Standard deviation
12016	Windsor West	51	0.045	0.045	0.124	0.177	0.276	0.428	0.045	0.136	0.098
14111	Sarnia	59	0.045	0.045	0.045	0.122	0.197	0.520	0.045	0.100	0.096
15026	London	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
26060	Kitchener	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
29000	Hamilton Downtown	43	0.045	0.045	0.102	0.174	0.252	0.842	0.045	0.137	0.142
48006	Newmarket	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

2022 1,3-butadiene annual statistics

Unit: micrograms per cubic metre (μg/m³)
1,3-Butadiene 24h AAQC: 10.0 μg/m³
1,3-Butadiene Annual AAQC: 2.0 μg/m³

ID	City	Number of samples	10%	25%	50%	75%	90%	Max	Min	Mean	Standard deviation	Number of times above 24h criteria	Number of times above annual criteria
12016	Windsor West	51	0.050	0.050	0.050	0.050	0.050	0.050	0.050	0.050	0.000	0	0
14111	Sarnia	59	0.050	0.050	0.050	0.050	0.050	0.296	0.050	0.062	0.043	0	0
15026	London	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
26060	Kitchener	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A
29000	Hamilton Downtown	43	0.050	0.050	0.050	0.050	0.050	0.148	0.050	0.052	0.015	0	0
48006	Newmarket	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

10-year trends

10-year trend for nitric oxide (NO)

Annual mean (ppb)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	3.7	4.0	3.5	3.1	3.3	3.2	2.7	1.7	2.5	2.4	-35.9
12016	Windsor West	3.6	3.8	4.2	2.9	2.6	2.6	3.1	1.7	2.3	2.4	-39.8
13001	Chatham	1.6	1.5	1.7	1.4	1.9	1.8	1.4	1.5	1.2	1.1	-11.0
14111	Sarnia	1.7	1.9	2.4	INS	1.5	1.8	1.7	1.6	1.9	2.0	N-SSS
15020	Grand Bend	1.0	0.2	0.3	0.5	0.3	0.2	0.3	0.4	0.4	0.2	N-SSS
15026	London	1.4	1.3	1.4	1.0	1.0	0.8	0.9	0.7	0.9	0.8	-35.5
21005	Brantford	1.2	0.9	1.3	0.8	0.8	1.0	0.9	0.8	0.7	0.7	-20.8
26060	Kitchener	1.6	1.6	1.6	1.3	1.0	0.9	1.2	0.7	0.9	1.1	-19.5
27067	St. Catharines	2.2	1.7	2.1	1.5	1.2	0.9	1.2	0.9	1.0	1.3	-38.5
28028	Guelph	1.1	1.2	1.3	1.1	1.1	1.2	0.9	0.8	1.0	0.9	-14.9
29000	Hamilton Downtown	4.3	3.9	1.3	4.2	3.9	3.9	4.0	2.9	3.5	3.5	-20.7
29118	Hamilton West	5.4	5.9	5.1	6.2	3.9	4.2	4.2	3.2	3.2	3.6	-44.9
29214	Hamilton Mountain	2.0	2.0	1.8	1.2	1.2	1.2	1.8	1.4	1.4	3.0	N-SSS
33003	Toronto East	5.7	6.2	5.8	5.4	4.4	3.1	3.4	2.3	2.4	2.5	-64.3
34021	Toronto North	4.1	4.3	3.9	3.5	3.0	2.5	2.7	2.1	2.8	2.3	-44.8
35125	Toronto West	8.6	9.5	9.2	8.2	7.7	6.7	7.5	5.2	6.0	5.9	-39.3
44008	Burlington	4.6	4.6	3.9	3.9	3.4	2.7	3.0	2.3	2.1	3.1	-42.4
44017	Oakville	2.1	3.4	2.7	1.8	1.7	1.8	1.8	1.3	1.6	1.7	-25.5
44029	Milton	2.8	3.1	3.5	4.2	2.3	3.6	3.6	2.7	2.6	3.1	N-SSS
45027	Oshawa	1.5	2.0	2.3	2.5	2.4	0.9	0.9	0.9	0.7	0.7	-73.0
46090	Brampton	4.6	4.0	3.8	3.4	2.2	2.2	2.2	1.4	1.5	1.9	-43.5
46108	Mississauga	3.1	2.9	3.1	3.6	2.0	1.6	2.6	1.4	1.6	2.2	-36.9
47045	Barrie	3.2	3.7	3.5	3.7	2.6	1.8	2.2	1.4	1.4	1.6	-72.7
48006	Newmarket	1.5	1.4	1.7	1.6	1.4	1.3	1.3	0.8	0.9	1.1	-40.7
49005	Parry Sound	0.5	0.6	0.8	0.6	0.5	0.5	0.7	0.4	0.5	0.6	N-SSS
51001	Ottawa Downtown	2.1	1.9	2.0	1.7	1.5	1.7	1.6	1.4	1.5	1.5	-9.3
52023	Kingston	0.2	0.8	0.9	0.7	0.6	0.6	0.6	0.7	0.7	0.6	N-SSS
54012	Belleville	1.7	1.2	1.5	1.8	1.1	1.0	1.3	1.4	1.3	1.2	-7.2
56051	Cornwall	1.9	1.5	1.8	2.1	1.2	1.4	1.5	1.2	1.4	1.6	-8.1
59006	Peterborough	1.7	1.8	1.5	1.3	1.2	0.9	1.2	1.0	0.8	0.9	-50.5
63203	Thunder Bay	4.7	4.2	5.2	3.8	4.1	3.8	3.8	3.4	3.5	4.1	-13.3
71078	Sault Ste. Marie	1.3	2.0	1.7	1.0	1.3	1.2	1.5	1.6	1.4	1.4	N-SSS
75010	North Bay	2.5	2.6	2.1	2.0	1.6	1.7	1.8	1.4	1.5	1.5	-36.9
77233	Sudbury	2.9	3.3	2.9	3.3	2.5	2.3	2.8	2.4	1.9	2.7	-25.6

Notes:

N/A indicates data not available.
INS indicates there was insufficient data to calculate a valid annual mean.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 15026 replaced station 15025 as the London site in 2013.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
Station 34021 replaced station 34020 as the Toronto North site in 2017.
Station 44029 was operated by the Halton Region prior to 2019.
Station 45027 replaced station 45026 as the Oshawa site in 2018.
Station 46090 replaced station 46089 as the Brampton site in 2017.
Station 52023 replaced station 52022 as the Kingston site in 2014.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for nitrogen dioxide (NO₂)

Annual mean (ppb)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	12.4	14.0	12.7	11.4	11.1	11.0	10.9	9.0	9.6	9.4	-29.5
12016	Windsor West	11.5	11.8	11.4	10.6	9.9	8.8	10.0	8.1	8.4	8.0	-34.6
13001	Chatham	6.0	6.8	6.8	5.4	6.1	5.1	5.8	5.1	5.1	4.5	-26.1
14111	Sarnia	8.1	9.0	9.3	INS	7.3	7.6	6.8	5.9	6.8	6.7	-25.7
15020	Grand Bend	4.4	3.1	3.4	2.8	3.0	3.3	2.5	2.3	2.4	2.7	-26.5
15026	London	6.4	6.9	6.6	5.4	5.8	5.4	5.8	4.5	5.2	5.0	-28.2
21005	Brantford	4.8	5.5	5.5	4.8	4.4	5.2	5.6	4.3	4.6	5.0	-8.1
26060	Kitchener	6.7	7.0	6.8	6.2	5.8	5.8	6.3	4.9	4.8	5.4	-26.4
27067	St. Catharines	7.7	7.3	7.3	6.6	6.6	6.0	6.0	5.3	5.8	5.7	-27.4
28028	Guelph	6.6	7.1	6.3	6.2	5.9	5.9	5.4	4.9	5.5	5.1	-27.7
29000	Hamilton Downtown	12.4	12.4	12.2	11.9	11.9	11.6	12.5	9.9	10.2	10.6	-19.5
29118	Hamilton West	12.7	12.8	12.2	11.8	10.4	11.0	11.3	9.5	10.1	9.8	-26.3
29214	Hamilton Mountain	9.0	9.3	9.0	7.9	7.8	7.8	8.8	6.9	6.3	6.1	-32.0
33003	Toronto East	13.6	14.2	13.9	12.1	11.5	10.6	10.2	8.4	9.5	9.9	-40.3
34021	Toronto North	12.9	13.4	12.9	12.0	10.5	10.4	10.5	8.9	9.3	10.2	-34.8
35125	Toronto West	16.1	17.1	16.6	15.7	15.0	14.4	14.6	12.1	12.9	13.2	-25.4
44008	Burlington	11.0	10.9	10.4	10.2	9.7	9.4	9.6	8.2	8.7	8.5	-25.9
44017	Oakville	9.2	8.2	7.5	8.2	8.2	8.5	9.1	6.8	7.3	7.8	-14.8
44029	Milton	8.5	8.4	9.4	9.3	7.7	9.8	8.9	7.6	8.2	8.3	N-SSS
45027	Oshawa	5.9	6.8	6.6	6.3	6.4	3.8	3.5	3.6	3.4	3.7	-52.6
46090	Brampton	9.1	10.6	9.9	9.7	8.3	8.1	8.6	6.8	6.5	7.2	-39.0
46108	Mississauga	9.5	9.2	9.2	8.6	8.0	7.2	8.4	6.7	7.0	7.5	-26.7
47045	Barrie	7.8	8.1	7.4	8.1	7.3	6.4	6.3	5.6	5.6	5.8	-31.9
48006	Newmarket	6.8	6.8	6.8	6.5	6.3	6.1	5.5	4.5	4.5	5.6	-33.3
49005	Parry Sound	2.9	3.3	3.2	2.9	2.7	2.9	2.6	2.4	2.5	2.4	-27.2
51001	Ottawa Downtown	7.9	7.4	7.4	6.9	7.1	7.3	6.7	5.9	5.7	6.1	-24.5
52023	Kingston	3.6	3.9	4.4	4.4	4.4	4.2	4.0	3.5	3.8	3.5	-15.5
54012	Belleville	4.7	4.5	4.8	5.1	4.3	3.7	4.2	3.5	3.8	4.2	-20.6
56051	Cornwall	6.2	5.6	5.3	5.5	5.0	5.1	5.0	4.6	4.8	5.1	-10.4
59006	Peterborough	5.0	5.3	5.1	4.5	4.7	4.5	3.9	4.1	4.1	4.5	-21.2
63203	Thunder Bay	7.3	7.8	7.5	7.1	6.7	7.5	6.7	6.1	6.5	7.0	-13.8
71078	Sault Ste. Marie	5.0	5.3	4.8	4.0	4.4	4.4	4.5	3.7	4.0	3.8	-24.6
75010	North Bay	5.8	5.6	5.6	4.7	4.6	4.9	5.1	4.3	3.9	4.1	-23.3
77233	Sudbury	7.2	7.3	7.2	7.0	6.8	6.5	6.9	6.3	5.6	6.1	-20.5

Notes:

N/A indicates data not available.
INS indicates there was insufficient data to calculate a valid annual mean.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 15026 replaced station 15025 as the London site in 2013.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
Station 34021 replaced station 34020 as the Toronto North site in 2017.
Station 44029 was operated by the Halton Region prior to 2019.
Station 45027 replaced station 45026 as the Oshawa site in 2018.
Station 46090 replaced station 46089 as the Brampton site in 2017.
Station 52023 replaced station 52022 as the Kingston site in 2014.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for nitrogen oxides (NO_x)

Annual mean (ppb)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	16.2	18.0	16.2	14.5	14.4	14.2	13.6	10.7	12.1	11.8	-31.1
12016	Windsor West	15.2	15.7	15.5	13.5	12.5	11.3	13.0	9.9	10.7	10.4	-35.8
13001	Chatham	7.7	8.2	8.5	6.8	8.0	6.9	7.2	6.6	6.3	5.6	-27.0
14111	Sarnia	9.8	10.9	11.7	INS	8.7	9.4	8.5	7.5	8.7	8.6	-19.4
15020	Grand Bend	5.4	3.4	3.8	3.3	3.4	3.4	2.7	2.7	2.8	2.9	-23.4
15026	London	7.8	8.3	8.0	6.5	6.8	6.2	6.6	5.2	6.1	5.8	-28.4
21005	Brantford	5.7	6.4	6.8	5.7	5.3	6.2	6.5	5.1	5.3	5.6	N-SSS
26060	Kitchener	8.3	8.5	8.4	7.5	6.9	6.7	7.4	5.5	5.7	6.5	-24.9
27067	St. Catharines	9.9	9.1	9.4	8.2	7.9	6.8	7.1	6.2	6.8	7.0	-30.3
28028	Guleph	7.8	8.4	7.7	7.3	7.0	7.1	6.4	5.6	6.5	6.0	-26.7
29000	Hamilton Downtown	16.8	16.3	7.7	16.1	15.8	15.5	16.5	12.8	13.7	14.0	-21.8
29118	Hamilton West	18.1	18.7	17.3	17.9	14.2	15.2	16.5	12.6	13.2	13.4	-34.9
29214	Hamilton Mountain	11.0	11.3	10.9	9.2	9.1	8.9	15.4	8.3	7.7	9.1	-25.7
33003	Toronto East	19.4	20.4	19.7	17.5	15.8	13.7	13.7	10.7	11.9	12.5	-48.3
34021	Toronto North	17.0	17.7	16.9	15.4	13.5	12.8	13.2	11.0	12.1	12.5	-39.8
35125	Toronto West	24.7	26.5	25.7	23.8	22.7	21.1	22.1	17.2	18.9	19.1	-31.6
44008	Burlington	15.6	15.5	14.3	14.2	13.2	12.0	12.6	10.5	10.7	11.5	-31.7
44017	Oakville	11.2	11.6	10.1	10.1	9.9	10.4	10.9	8.0	8.8	9.5	-22.2
44029	Milton	11.8	12.0	13.2	13.5	10.0	13.4	12.5	10.3	10.8	11.3	N-SSS
45027	Oshawa	7.4	8.8	8.9	8.8	8.8	4.7	4.4	4.5	4.1	4.3	-56.8
46090	Brampton	13.9	14.6	13.7	13.1	10.6	10.3	10.74	8.1	8.0	9.1	-44.6
46108	Mississauga	12.6	12.1	12.3	12.2	9.9	8.8	10.97	8.0	8.6	9.7	-27.9
47045	Barrie	11.0	11.8	10.9	11.9	9.9	8.3	8.52	6.9	7.0	7.4	-43.9
48006	Newmarket	8.4	8.2	8.5	8.1	7.8	7.4	6.78	5.2	5.4	6.7	-35.2
49005	Parry Sound	3.4	4.0	4.0	3.6	3.3	3.3	3.34	2.8	3.1	3.0	-26.4
51001	Ottawa Downtown	10.1	9.3	9.5	8.6	8.6	9.0	8.31	7.3	7.2	7.5	-22.9
52023	Kingston	3.8	4.8	5.3	5.2	4.9	4.7	4.55	4.1	4.5	4.1	-18.2
54012	Belleville	6.3	5.7	6.2	6.7	5.4	4.7	5.53	4.9	5.1	5.4	-18.0
56051	Cornwall	8.0	7.0	7.1	7.6	6.2	6.3	6.54	5.8	6.2	6.7	-11.8
59006	Peterborough	6.6	7.1	6.6	5.9	5.8	5.3	5.14	5.0	4.8	5.4	-27.9
63203	Thunder Bay	12.0	11.9	12.7	11	10.8	11.3	10.44	9.5	10.0	11.1	-15.0
71078	Sault Ste. Marie	6.3	7.3	6.6	5.1	5.8	5.6	5.95	5.2	5.3	5.2	-22.3
75010	North Bay	8.3	8.1	7.8	6.7	6.2	6.6	6.91	5.6	5.4	5.7	-26.9
77233	Sudbury	10.1	10.6	10.2	10.2	9.4	8.8	9.7	8.7	7.5	8.8	-21.9

Notes:

N/A indicates data not available.
INS indicates there was insufficient data to calculate a valid annual mean.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 15026 replaced station 15025 as the London site in 2013.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
Station 34021 replaced station 34020 as the Toronto North site in 2017.
Station 44029 was operated by the Halton Region prior to 2019.
Station 45027 replaced station 45026 as the Oshawa site in 2018.
Station 46090 replaced station 46089 as the Brampton site in 2017.
Station 52023 replaced station 52022 as the Kingston site in 2014.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for fine particulate matter (PM_2.5)

Annual mean (µg/m³)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	9.2	10.1	9.3	8.1	7.8	8.5	7.8	7.1	8.3	7.8	-20.4
12016	Windsor West	10.0	10.7	9.9	8.5	8.5	8.7	9.1	8.8	9.6	8.8	-8.4
13001	Chatham	8.1	8.6	8.1	6.6	6.4	6.8	6.8	6.7	7.1	6.7	-15.9
14111	Sarnia	8.5	9.0	8.4	INS	7.0	7.4	7.1	7.1	7.7	7.1	-16.5
15020	Grand Bend	7.3	8.1	7.7	6.0	5.1	5.6	5.4	4.8	5.7	5.6	-34.2
15026	London	9.1	8.8	8.3	7.1	7.0	7.3	6.7	6.5	7.8	7.1	-20.7
16015	Port Stanley	7.4	8.2	8.0	6.5	6.3	6.8	6.7	6.5	7.0	6.8	-14.6
18007	Tiverton	5.8	6.5	6.4	5.1	5.1	5.7	5.0	4.8	5.4	4.6	-19.9
21005	Brantford	8.5	9.2	8.7	7.3	7.2	7.7	7.4	6.7	7.7	7.0	-19.7
26060	Kitchener	8.7	9.3	8.8	7.3	7.0	7.4	7.2	6.6	7.8	7.5	-19.8
27067	St. Catharines	8.5	8.8	8.4	6.9	7.0	7.0	7.0	6.3	6.5	5.4	-34.3
28028	Guelph	8.1	8.9	8.4	6.9	6.8	7.4	7.1	6.9	7.7	6.7	-16.3
29000	Hamilton Downtown	10.1	10.8	10.2	8.2	8.5	9.2	8.8	8.1	8.9	8.6	-20.7
29118	Hamilton West	9.6	9.9	9.9	7.9	7.5	8.2	7.8	7.8	8.0	7.3	-25.5
29214	Hamilton Mountain	9.2	9.4	9.0	7.2	7.4	7.7	7.9	7.1	8.0	7.7	-18.0
33003	Toronto East	8.2	8.9	8.5	7.0	7.4	7.2	7.0	6.7	7.4	6.7	-21.0
34021	Toronto North	8.3	9.2	9.4	7.3	7.4	7.6	6.8	6.4	7.4	6.8	-26.5
35125	Toronto West	8.8	9.1	8.5	7.0	7.4	7.7	7.2	6.9	7.7	6.9	-19.7
44008	Burlington	8.7	9.6	9.4	7.6	7.0	7.2	7.0	6.4	7.2	6.6	-31.1
44017	Oakville	8.0	8.5	8.3	7.0	6.9	7.4	7.2	6.3	7.1	6.7	-17.0
44029	Milton	8.5	10.3	8.8	7.1	7.0	7.5	7.5	7.1	7.6	6.9	0.0
45027	Oshawa	7.4	7.7	7.5	5.9	5.9	6.4	6.1	6.2	6.2	5.7	-21.4
46090	Brampton	8.5	8.9	8.4	6.8	7.0	7.3	6.8	6.7	7.2	7.1	-20.4
46108	Mississauga	7.9	8.7	8.5	7.2	6.8	7.3	7.0	6.6	7.6	7.1	-17.0
47045	Barrie	7.5	7.6	7.6	6.5	7.0	7.7	7.5	6.8	6.9	6.4	-12.2
48006	Newmarket	7.3	7.3	7.1	6.0	5.9	6.4	5.9	5.9	6.5	6.2	-15.7
49005	Parry Sound	5.8	5.8	5.7	4.8	4.6	5.0	4.4	4.4	5.0	4.7	-21.5
49010	Dorset	5.4	5.3	5.6	4.6	4.6	4.9	4.1	4.5	4.7	4.5	-16.8
51001	Ottawa Downtown	7.0	7.0	6.9	5.9	5.9	5.9	5.9	6.0	6.3	5.9	-16.0
52023	Kingston	6.5	6.8	6.3	5.8	5.3	5.6	5.4	5.6	6.5	5.3	-12.5
54012	Belleville	6.9	6.8	6.6	5.5	5.8	6.4	6.1	6.3	6.0	5.5	-11.5
56051	Cornwall	7.7	7.0	6.9	6.4	5.9	6.3	5.9	6.0	6.5	6.4	-13.0
59006	Peterborough	7.4	6.9	6.8	5.8	5.8	6.3	6.0	5.6	6.5	6.6	-14.4
63203	Thunder Bay	6.3	6.6	6.5	4.9	5.1	6.0	5.1	5.5	6.6	5.0	-15.6
71078	Sault Ste. Marie	5.6	6.0	5.9	4.9	5.0	5.5	4.8	4.5	5.8	4.5	-19.8
75010	North Bay	5.2	5.3	5.3	4.6	4.6	5.5	4.5	4.6	5.7	5.1	N-SSS
77233	Sudbury	5.7	6.0	6.3	5.4	5.0	5.4	5.0	5.1	5.8	5.2	-15.4

Notes:

Measurements taken by Synchronized Hybrid Ambient Real-time Particulate (SHARP) 5030.
INS indicates there was insufficient data in any one quarter to calculate a valid annual mean.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 15026 replaced station 15025 as the London site in 2013.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
Station 34021 replaced station 34020 as the Toronto North site in 2017.
Station 44029 was operated by the Halton Region prior to 2019.
Station 45027 replaced station 45026 as the Oshawa site in 2018.
Station 46090 replaced station 46089 as the Brampton site in 2017.
Station 52023 replaced station 52022 as the Kingston site in 2014.
Station 77233 replaced station 77219 as the Sudbury site in 2013.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for ground-level ozone (O₃) 1h maximum

1h Maximum (ppb)
O₃ 1h AAQC: 80 ppb

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	89	78	89	95	78	89	82	81	82	84	N-SSS
12016	Windsor West	87	86	87	95	82	90	80	83	86	81	N-SSS
13001	Chatham	85	78	79	84	90	78	76	77	75	85	N-SSS
14111	Sarnia	83	79	83	83	80	101	87	82	97	97	N-SSS
15020	Grand Bend	86	90	87	91	82	100	85	93	104	92	N-SSS
15026	London	82	82	77	82	78	76	70	77	78	89	N-SSS
16015	Port Stanley	85	87	86	84	90	86	77	76	74	89	N-SSS
18007	Tiverton	92	86	83	85	82	104	81	75	78	85	N-SSS
21005	Brantford	74	80	79	84	74	76	74	74	79	90	N-SSS
26060	Kitchener	72	76	76	81	75	75	77	74	81	79	N-SSS
27067	St. Catharines	96	70	73	80	73	75	70	75	73	84	N-SSS
28028	Guelph	73	79	79	82	76	78	74	70	83	82	N-SSS
29000	Hamilton Downtown	86	74	74	78	73	77	65	77	80	84	N-SSS
29118	Hamilton West	78	70	71	78	74	76	65	76	78	82	N-SSS
29214	Hamilton Mountain	86	79	79	76	81	80	70	79	80	81	N-SSS
33003	Toronto East	87	73	91	99	82	72	67	77	78	77	N-SSS
34021	Toronto North	87	82	90	85	82	83	77	95	86	81	N-SSS
35125	Toronto West	83	72	82	79	82	76	77	81	81	70	N-SSS
44008	Burlington	92	73	84	80	88	83	74	86	80	79	N-SSS
44017	Oakville	101	72	80	74	84	82	71	81	84	83	N-SSS
44029	Milton	93	80	80	79	74	81	77	77	84	81	N-SSS
45027	Oshawa	96	73	73	81	86	76	66	88	80	80	N-SSS
46090	Brampton	84	80	84	79	75	83	72	83	84	75	N-SSS
46108	Mississauga	83	76	79	79	78	79	65	80	81	80	N-SSS
47045	Barrie	73	68	80	79	75	72	75	70	82	71	N-SSS
48006	Newmarket	72	87	92	94	85	91	88	87	81	90	N-SSS
49005	Parry Sound	77	74	86	74	74	80	68	73	80	73	N-SSS
49010	Dorset	69	79	78	74	69	77	64	66	70	64	N-SSS
51001	Ottawa Downtown	67	64	69	73	71	72	57	64	68	61	N-SSS
52023	Kingston	79	81	74	82	94	78	68	72	78	79	N-SSS
54012	Belleville	92	80	77	96	86	85	73	81	82	96	N-SSS
56051	Cornwall	73	70	69	74	72	68	58	62	70	66	N-SSS
59006	Peterborough	74	74	78	85	80	86	68	87	85	79	N-SSS
63203	Thunder Bay	63	70	62	62	51	63	56	56	65	58	N-SSS
71078	Sault Ste. Marie	66	73	75	80	70	69	61	77	66	75	N-SSS
75010	North Bay	72	71	70	78	69	63	63	74	71	72	N-SSS
77233	Sudbury	76	73	67	80	69	70	75	62	56	64	N-SSS

Notes:

Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 15026 replaced station 15025 as the London site in 2013.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
Station 34021 replaced station 34020 as the Toronto North site in 2017.
Station 44029 was operated by the Halton Region prior to 2019.
Station 45027 replaced station 45026 as the Oshawa site in 2018.
Station 46090 replaced station 46089 as the Brampton site in 2017.
Station 52023 replaced station 52022 as the Kingston site in 2014.
Station 77233 replaced station 77219 as the Sudbury site in 2013.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for ground-level ozone (O₃)

Annual mean (ppb)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	26.9	26.0	27.0	27.7	27.3	26.9	26.6	27.3	28.8	30.4	10.4
12016	Windsor West	26.7	27.2	26.5	27.7	27.0	27.0	27.3	26.0	29.4	29.5	9.2
13001	Chatham	29.6	29.3	29.6	29.6	29.5	28.7	29.2	29.1	30.4	31.6	N-SSS
14111	Sarnia	28.6	27.1	27.8	28.8	28.4	29.0	29.2	26.7	30.2	31.0	5.4
15020	Grand Bend	32.3	31.0	30.4	30.7	31.0	31.5	31.6	30.9	32.0	31.9	N-SSS
15026	London	28.7	28.1	27.9	28.2	28.1	27.6	26.8	27.7	28.9	29.6	N-SSS
16015	Port Stanley	33.9	32.3	32.8	32.9	33.0	32.3	32.3	30.9	31.4	31.1	-6.0
18007	Tiverton	32.4	31.8	32.5	33.1	32.4	32.3	31.1	30.5	32.4	31.9	N-SSS
21005	Brantford	29.0	29.4	28.9	29.5	28.3	28.3	27.5	28.0	28.5	29.0	N-SSS
26060	Kitchener	28.0	27.3	27.9	28.8	28.1	27.7	27.2	27.7	28.4	28.9	N-SSS
27067	St. Catharines	28.6	28.5	28.6	29.8	28.1	28.5	28.4	30.2	29.8	29.8	4.1
28028	Guelph	29.0	27.8	27.7	28.7	28.4	28.9	26.3	27.0	29.5	30.9	N-SSS
29000	Hamilton Downtown	25.0	25.3	25.9	26.7	25.6	25.6	24.4	26.3	26.4	25.9	N-SSS
29118	Hamilton West	24.4	22.7	23.9	24.4	25.0	25.5	23.6	25.2	24.9	25.2	N-SSS
29214	Hamilton Mountain	29.5	29.1	29.4	29.5	29.1	29.3	27.5	29.3	28.7	28.2	N-SSS
33003	Toronto East	24.1	23.4	23.5	25.5	24.4	25.2	24.6	26.1	26.2	25.1	9.8
34021	Toronto North	25.3	25.3	25.7	25.9	24.0	25.5	24.1	26.0	26.4	24.3	N-SSS
35125	Toronto West	21.5	21.1	21.3	22.1	22.1	22.3	21.8	23.4	22.8	22.0	7.3
44008	Burlington	26.4	25.5	26.5	27.6	27.1	27.6	26.6	28.3	27.4	26.6	5.0
44017	Oakville	28.3	27.2	27.4	27.1	27.4	28.7	27.1	28.0	28.8	28.1	N-SSS
44029	Milton	27.6	27.1	27.2	27.2	27.5	28.1	26.9	26.8	27.2	27.6	N-SSS
45027	Oshawa	27.2	27.2	26.2	27.2	27.9	25.8	24.4	26.4	26.9	26.6	N-SSS
46090	Brampton	26.7	26.5	26.5	27.1	27.2	28.6	26.5	28.4	28.3	27.0	5.6
46108	Mississauga	25.2	25.4	25.4	26.0	26.2	26.1	24.5	25.6	26.2	25.7	N-SSS
47045	Barrie	25.5	25.6	25.4	25.9	25.9	27.5	25.7	25.9	25.0	25.3	N-SSS
48006	Newmarket	28.7	28.6	28.5	28.6	27.9	29.8	27.8	28.5	30.2	28.1	N-SSS
49005	Parry Sound	30.4	29.6	30.4	29.6	29.7	30.8	29.8	29.9	30.3	29.9	N-SSS
49010	Dorset	28.1	27.7	27.0	27.4	26.9	28.2	27.5	27.1	26.8	26.3	N-SSS
51001	Ottawa Downtown	25.6	24.8	25.6	25.6	25.5	26.4	25.9	25.2	25.8	26.1	N-SSS
52023	Kingston	30.3	31.4	30.3	30.5	30.4	30.5	29.9	30.1	30.2	29.9	-3.1
54012	Belleville	29.2	29.6	29.6	30.5	30.2	29.9	29.6	29.7	30.3	30.3	N-SSS
56051	Cornwall	26.9	27.3	27.9	27.1	27.2	27.6	26.9	26.4	26.7	26.3	N-SSS
59006	Peterborough	28.6	29.2	29.3	29.7	28.9	29.7	28.3	27.6	28.6	27.4	N-SSS
63203	Thunder Bay	26.3	23.4	24.0	23.2	23.4	24.3	23.7	22.9	24.4	24.6	N-SSS
71078	Sault Ste. Marie	28.9	28.4	27.8	27.3	28.1	29.7	28.1	28.2	29.2	28.8	N-SSS
75010	North Bay	27.4	26.7	27.0	26.4	26.4	26.0	26.4	26.2	26.4	27.2	N-SSS
77233	Sudbury	27.2	26.3	25.7	25.1	25.9	27.1	26.3	24.8	23.9	25.6	N-SSS

Notes:

Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 15026 replaced station 15025 as the London site in 2013.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
Station 34021 replaced station 34020 as the Toronto North site in 2017.
Station 44029 was operated by the Halton Region prior to 2019.
Station 45027 replaced station 45026 as the Oshawa site in 2018.
Station 46090 replaced station 46089 as the Brampton site in 2017.
Station 52023 replaced station 52022 as the Kingston site in 2014.
Station 77233 replaced station 77219 as the Sudbury site in 2013.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for ground-level ozone (O₃) summer means (May - September)

Summer mean (ppb)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	32.5	30.9	33.3	33.4	32.8	33.7	31.4	32.7	33.8	35.3	N-SSS
12016	Windsor West	30.9	30.9	31.8	33.0	31.8	32.4	31.2	30.6	33.8	34.0	N-SSS
13001	Chatham	34.2	32.4	34.4	32.9	33.1	32.1	31.9	32.5	33.6	35.0	N-SSS
14111	Sarnia	32.0	29.4	31.1	32.1	32.0	34.0	31.5	30.1	35.1	33.8	N-SSS
15020	Grand Bend	33.1	31.5	32.3	32.0	32.1	32.7	31.7	31.7	33.1	32.2	N-SSS
15026	London	30.9	29.5	31.0	30.4	29.8	30.5	27.4	29.1	31.0	31.0	N-SSS
16015	Port Stanley	36.9	33.7	35.6	35.2	35.0	35.3	33.7	32.8	34.3	32.7	-8.3
18007	Tiverton	32.5	30.8	33.3	34.1	32.2	32.9	29.7	30.5	33.0	31.9	N-SSS
21005	Brantford	30.1	29.9	31.2	32.2	29.4	30.4	28.3	29.5	31.1	30.7	N-SSS
26060	Kitchener	29.8	28.5	30.2	31.8	29.8	30.6	29.2	29.6	30.6	30.5	N-SSS
27067	St. Catharines	31.2	29.5	31.7	33.2	29.8	31.3	29.7	32.6	32.9	31.5	N-SSS
28028	Guelph	30.4	28.9	30.2	31.2	29.6	31.7	27.3	29.0	31.1	32.8	N-SSS
29000	Hamilton Downtown	28.4	27.5	29.5	30.6	27.8	29.7	26.1	29.4	30.1	28.3	N-SSS
29118	Hamilton West	26.4	22.7	26.5	27.1	26.8	28.5	24.4	27.7	27.9	26.8	N-SSS
29214	Hamilton Mountain	32.5	31.6	33.9	33.2	31.5	34.0	29.6	32.3	32.3	30.6	N-SSS
33003	Toronto East	27.1	25.9	27.7	29.7	26.0	29.2	26.0	28.8	29.2	27.2	N-SSS
34021	Toronto North	29.4	28.6	30.7	30.7	26.3	30.4	25.9	29.3	29.8	27.1	N-SSS
35125	Toronto West	24.4	23.5	25.0	25.9	24.3	26.3	24.3	25.9	25.9	24.3	N-SSS
44008	Burlington	29.2	27.4	30.1	30.5	29.0	31.8	28.8	31.2	30.4	28.9	N-SSS
44017	Oakville	30.6	28.3	30.2	29.9	29.5	32.4	28.8	30.4	32.1	30.7	N-SSS
44029	Milton	30.6	28.2	30.4	30.6	29.6	34.3	28.9	28.6	30.6	30.2	N-SSS
45027	Oshawa	28.3	27.9	28.9	29.4	28.6	26.6	24.4	27.4	27.4	25.1	N-SSS
46090	Brampton	29.5	28.9	30.3	31.2	29.5	32.7	28.2	31.0	31.6	29.9	N-SSS
46108	Mississauga	26.5	26.5	28.0	28.5	27.2	28.3	24.9	27.0	28.5	27.4	N-SSS
47045	Barrie	25.6	25.4	26.8	27.4	25.6	29.0	24.7	25.8	25.1	25.0	N-SSS
48006	Newmarket	30.3	29.4	31.2	31.7	29.0	33.2	28.4	30.1	32.2	29.8	N-SSS
49005	Parry Sound	30.1	28.2	31.4	28.9	27.7	30.9	27.8	28.5	30.0	29.1	N-SSS
49010	Dorset	25.3	24.4	24.6	25.1	23.0	25.8	23.9	23.7	24.1	22.8	N-SSS
51001	Ottawa Downtown	26.5	24.6	27.8	27.5	25.3	27.6	25.6	25.7	27.4	26.2	N-SSS
52023	Kingston	32.4	32.7	32.2	33.3	30.9	33.1	30.0	31.3	32.0	30.6	N-SSS
54012	Belleville	30.6	30.4	33.2	33.7	30.9	32.4	30.0	31.0	32.8	31.4	N-SSS
56051	Cornwall	28.1	27.0	29.7	28.7	27.1	29.4	26.1	26.3	27.8	25.6	N-SSS
59006	Peterborough	29.5	30.0	31.5	32.3	29.2	32.2	28.1	28.4	29.9	27.9	N-SSS
63203	Thunder Bay	24.7	22.7	23.6	22.0	20.4	22.1	21.8	21.3	24.4	22.9	N-SSS
71078	Sault Ste. Marie	28.2	27.4	28.1	26.3	26.3	29.1	26.2	26.4	28.8	27.0	N-SSS
75010	North Bay	26.9	26.2	27.8	26.4	24.7	26.3	25.7	24.4	27.4	26.3	N-SSS
77233	Sudbury	28.0	27.0	27.7	26.6	25.8	28.8	25.9	23.7	23.4	26.0	N-SSS

Notes:

Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 15026 replaced station 15025 as the London site in 2013.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
Station 34021 replaced station 34020 as the Toronto North site in 2017.
Station 44029 was operated by the Halton Region prior to 2019.
Station 45027 replaced station 45026 as the Oshawa site in 2018.
Station 46090 replaced station 46089 as the Brampton site in 2017.
Station 52023 replaced station 52022 as the Kingston site in 2014.
Station 77233 replaced station 77219 as the Sudbury site in 2013.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for ground-level ozone (O₃) winter means (January-April, October-December)

Winter mean (ppb)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	22.8	22.8	22.4	23.6	23.3	22.4	23.1	23.5	25.19	26.9	N-SSS
12016	Windsor West	23.4	24.5	22.7	23.9	23.6	23.1	24.4	22.8	26.32	26.3	N-SSS
13001	Chatham	26.2	27.1	26.3	27.2	26.8	26.2	27.4	26.7	28.21	29.2	N-SSS
14111	Sarnia	26.2	25.4	25.4	INS	26.0	25.4	27.6	24.3	26.26	29.1	N-SSS
15020	Grand Bend	31.8	30.6	29.1	29.8	30.2	30.7	31.6	30.5	31.32	31.7	N-SSS
15026	London	26.9	27.1	25.8	26.6	26.9	25.6	26.4	26.7	27.49	28.6	N-SSS
16015	Port Stanley	31.8	31.3	31.2	31.2	31.5	30.2	31.4	29.6	29.37	30.0	-7.8
18007	Tiverton	32.4	32.7	31.9	32.4	32.6	31.9	32.1	30.6	32.0	31.9	N-SSS
21005	Brantford	28.3	28.8	27.2	27.7	27.5	26.7	26.9	27.0	26.8	27.8	N-SSS
26060	Kitchener	26.7	26.5	26.1	26.6	27.1	25.6	25.8	26.4	26.93	27.9	N-SSS
27067	St. Catharines	26.8	27.9	26.3	27.2	27.0	26.4	27.5	28.5	27.8	28.6	N-SSS
28028	Guelph	28.0	27.0	26.0	26.8	27.5	26.9	25.7	25.6	28.5	29.6	N-SSS
29000	Hamilton Downtown	22.5	23.7	23.3	23.9	24.2	22.6	23.2	24.1	23.82	24.3	N-SSS
29118	Hamilton West	23.0	22.8	22.1	22.5	23.7	23.3	23.0	23.5	22.85	24.1	N-SSS
29214	Hamilton Mountain	27.3	27.3	26.3	26.8	27.4	25.9	25.9	27.2	26.21	26.5	N-SSS
33003	Toronto East	22.0	21.6	20.5	22.5	23.3	22.4	23.5	24.2	24.07	23.7	12.9
34021	Toronto North	22.3	22.8	22.1	22.6	22.3	22.0	22.8	23.7	23.8	22.3	N-SSS
35125	Toronto West	19.5	19.4	18.6	19.4	20.5	19.4	20.1	21.6	20.74	20.4	9.1
44008	Burlington	24.4	24.1	23.8	25.6	25.7	24.7	25.2	26.2	25.29	25.0	N-SSS
44017	Oakville	26.6	26.5	25.3	25.1	25.9	26.0	26.0	26.3	26.49	26.3	N-SSS
44029	Milton	25.5	26.3	24.9	24.7	25.9	24.9	25.5	25.6	24.81	25.6	N-SSS
45027	Oshawa	26.4	26.7	24.3	25.6	27.3	25.4	24.5	25.7	26.73	27.8	N-SSS
46090	Brampton	24.6	24.8	23.8	24.1	25.6	25.6	25.3	26.5	26.1	25.0	N-SSS
46108	Mississauga	24.3	24.7	23.6	24.2	25.5	24.6	24.2	24.7	24.67	24.5	N-SSS
47045	Barrie	25.5	25.8	24.4	24.8	26.3	26.5	26.4	26.1	25.07	25.6	N-SSS
48006	Newmarket	27.5	28.1	26.6	26.3	27.2	27.3	27.3	27.5	28.78	26.9	N-SSS
49005	Parry Sound	30.6	30.6	29.8	30.0	31.1	30.7	31.3	31.0	30.6	30.5	N-SSS
49010	Dorset	30.1	30.1	28.8	29.0	29.6	30.0	30.1	29.5	28.84	28.8	N-SSS
51001	Ottawa Downtown	24.9	25.1	24.0	24.3	25.6	25.5	26.2	24.9	24.68	26.0	N-SSS
52023	Kingston	28.8	30.4	28.9	28.5	30.2	28.6	29.9	29.2	28.94	29.5	N-SSS
54012	Belleville	28.2	29.1	27.0	28.2	29.7	28.1	29.3	28.7	28.67	29.6	N-SSS
56051	Cornwall	25.7	27.6	26.6	26.0	27.4	26.3	27.5	26.5	26.0	26.9	N-SSS
59006	Peterborough	28.0	28.6	27.7	27.8	28.7	27.9	28.5	27.3	27.72	27.1	N-SSS
63203	Thunder Bay	27.4	23.8	24.2	24.2	25.6	25.9	25.1	24.1	24.4	25.6	N-SSS
71078	Sault Ste. Marie	29.4	29.2	27.7	28.0	29.5	30.2	29.5	29.6	29.54	30.1	2.3
75010	North Bay	27.8	27.1	26.4	26.4	27.6	25.9	26.9	27.4	26.23	27.9	N-SSS
77233	Sudbury	26.6	25.8	24.3	24.0	26.1	26.0	26.7	25.7	24.39	25.4	N-SSS

Notes:

Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 15026 replaced station 15025 as the London site in 2013.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
Station 34021 replaced station 34020 as the Toronto North site in 2017.
Station 44029 was operated by the Halton Region prior to 2019.
Station 45027 replaced station 45026 as the Oshawa site in 2018.
Station 46090 replaced station 46089 as the Brampton site in 2017.
Station 52023 replaced station 52022 as the Kingston site in 2014.
Station 77233 replaced station 77219 as the Sudbury site in 2013.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for sulphur dioxide (SO₂)

Annual mean (ppb)
SO₂ 1y AAQC: 4 ppb

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	2.4	2.4	1.9	1.1	1.0	0.6	0.4	0.3	0.4	0.5	-81.3
12016	Windsor West	2.6	2.8	1.9	1.4	0.9	0.7	0.8	0.8	0.7	0.7	-63.0
14111	Sarnia	3.8	3.5	3.2	INS	1.7	1.9	1.9	2.0	2.2	2.5	-30.0
29000	Hamilton Downtown	4.8	5.1	4.3	3.2	3.5	5.0	4.8	3.7	3.8	3.7	-14.3
29214	Hamilton Mountain	2.8	2.9	2.6	1.8	1.8	2.4	3.5	2.5	3.2	3.1	N-SSS
35125	Toronto West	0.6	0.7	1.0	0.6	0.5	0.3	0.3	0.2	0.2	0.3	-79.0
51001	Ottawa Downtown	0.3	0.3	0.4	0	0.1	0.2	0.2	0.1	0.2	0.3	N-SSS
71078	Sault Ste. Marie	0.8	0.8	0.8	0.6	0.7	0.8	0.7	0.6	0.8	0.8	N-SSS
77233	Sudbury	2.8	2.4	2.4	2.1	1.3	1.2	1.2	0.9	0.9	1.1	-64.8

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
Station 29214 replaced station 29114 as the Hamilton Mountain site in 2019.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for carbon monoxide (CO)

1h maximum (ppm)
CO 1h AAQC: 30 ppm

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12008	Windsor Downtown	1.9	1.8	1.9	2.3	2.6	1.9	2.3	1.2	1.6	0.22	N-SSS
29000	Hamilton Downtown	2.0	2.9	1.3	1.4	2.1	1.7	1.9	1.2	1.5	0.23	N-SSS
35125	Toronto West	1.4	1.6	1.3	1.7	1.2	0.9	1.5	1.6	1.2	0.21	N-SSS
51001	Ottawa Downtown	0.9	0.8	0.8	0.9	0.7	1.0	0.7	0.9	0.8	0.24	N-SSS

Note:

N-SSS - Non-Significant Sen's Slope (significant trend not detected).

10-year trend for benzene

Annual mean (µg/m³)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12016	Windsor West	0.519	0.610	0.566	0.521	0.450	0.478	0.445	N/A	0.527	0.369	-28.4
14111	Sarnia	0.820	1.007	1.191	0.689	0.604	0.574	0.419	N/A	0.570	0.427	-48.8
15026	London	0.413	0.446	0.451	0.341	0.339	0.321	0.296	N/A	N/A	N/A	-55.4
26060	Kitchener	N/A	0.483	0.548	0.395	0.446	0.355	0.290	N/A	N/A	N/A	-61.4
29000	Hamilton Downtown	INS	0.899	1.092	0.675	0.569	0.639	0.568	N/A	0.613	0.706	-36.0
48006	Newmarket	0.406	0.422	0.425	0.328	0.385	INS	0.250	N/A	N/A	N/A	-49.4

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N/A indicates data not available.
The 2016 average for Sarnia is derived from data from May to December 2016.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.

10-year trend for toluene

Annual mean (µg/m³)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12016	Windsor West	1.017	1.542	1.248	1.272	0.972	1.131	0.797	N/A	1.085	0.730	-41.1
14111	Sarnia	1.587	1.908	2.350	1.778	1.550	1.014	0.779	N/A	1.053	0.895	-53.5
15026	London	0.887	0.839	1.013	0.727	0.633	0.657	0.491	N/A	N/A	N/A	-70.5
26060	Kitchener	N/A	1.278	1.052	1.020	1.002	0.625	0.572	N/A	N/A	N/A	-77.7
29000	Hamilton Downtown	INS	2.229	2.249	1.642	1.296	0.862	0.817	N/A	1.314	0.872	-62.5
48006	Newmarket	0.916	0.732	1.340	1.118	0.807	INS	0.418	N/A	N/A	N/A	-52.0

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N/A indicates data not available.
The 2016 average for Sarnia is derived from data from May to December 2016.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.

10-year trend for ethylbenzene

Annual mean (µg/m³)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12016	Windsor West	0.179	0.267	0.238	0.234	0.181	0.187	0.137	N/A	0.328	0.126	-46.9
14111	Sarnia	0.255	0.253	0.362	0.282	0.211	0.235	0.118	N/A	0.187	0.127	-50.0
15026	London	0.125	0.121	0.149	0.108	0.105	0.141	0.070	N/A	N/A	N/A	-56.7
26060	Kitchener	N/A	0.167	0.168	0.159	0.164	0.109	0.079	N/A	N/A	N/A	-67.3
29000	Hamilton Downtown	INS	0.192	0.210	0.186	0.187	0.129	0.126	N/A	0.172	0.122	-42.3
48006	Newmarket	0.134	0.125	0.249	0.215	0.130	INS	0.067	N/A	N/A	N/A	-47.2

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N/A indicates data not available.
The 2016 average for Sarnia is derived from data from May to December 2016.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.

10-year trend for m- and p-xylene

Annual mean (µg/m³)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12016	Windsor West	0.536	0.825	0.702	0.635	0.505	0.502	0.409	N/A	0.619	0.359	-51.6
14111	Sarnia	0.510	0.629	0.850	0.495	0.499	0.563	0.256	N/A	0.319	0.272	-44.0
15026	London	0.345	0.318	0.398	0.267	0.268	0.407	0.200	N/A	N/A	N/A	-52.3
26060	Kitchener	N/A	0.469	0.464	0.434	0.451	0.276	0.223	N/A	N/A	N/A	-69.4
29000	Hamilton Downtown	INS	0.594	0.621	0.518	0.532	0.359	0.398	N/A	0.486	0.383	-43.8
48006	Newmarket	0.362	0.334	0.582	0.484	0.350	INS	0.191	N/A	N/A	N/A	-53.1

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N/A indicates data not available.
The 2016 average for Sarnia is derived from data from May to December 2016.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.

10-year trend for o-xylene

Annual mean (µg/m³)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12016	Windsor West	0.184	0.283	0.239	0.232	0.190	0.184	0.147	N/A	0.246	0.136	-38.9
14111	Sarnia	0.171	0.226	0.313	0.178	0.192	0.213	0.101	N/A	0.122	0.100	-43.2
15026	London	0.118	0.113	0.146	0.103	0.103	0.148	0.074	N/A	N/A	N/A	-42.4
26060	Kitchener	N/A	0.166	0.164	0.153	0.164	0.107	0.082	N/A	N/A	N/A	-69.2
29000	Hamilton Downtown	INS	0.206	0.216	0.189	0.198	0.131	0.145	N/A	0.183	0.137	-32.8
48006	Newmarket	0.126	0.134	0.218	0.192	0.128	INS	0.068	N/A	N/A	N/A	-61.0

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N/A indicates data not available.
The 2016 average for Sarnia is derived from data from May to December 2016.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.

10-year trend for 1,3-butadiene

Annual mean (µg/m³)

ID	City/Town	2013	2014	2015	2016	2017	2018	2019	2020	2021	2022	Change over 10 year (%)
12016	Windsor West	0.036	0.042	0.035	0.032	0.034	0.028	0.028	N/A	0.038	0.050	N-SSS
14111	Sarnia	0.209	0.124	0.216	0.089	0.077	0.088	0.054	N/A	0.071	0.062	-63.4
15026	London	0.023	0.025	0.026	0.020	0.035	0.025	0.025	N/A	N/A	N/A	N-SSS
26060	Kitchener	N/A	0.029	0.029	0.023	0.038	0.026	0.025	N/A	N/A	N/A	N-SSS
29000	Hamilton Downtown	INS	0.032	0.037	0.025	0.039	0.028	0.028	N/A	0.036	0.052	24.4
48006	Newmarket	0.021	0.020	0.028	0.024	0.035	INS	0.025	N/A	N/A	N/A	62.8

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N/A indicates data not available.
The 2016 average for Sarnia is derived from data from May to December 2016.
Station 14111 replaced station 14064 as the Sarnia site in 2016.
The 2018 average for Windsor West is derived from data from February to July, and October to December in 2018.
The 2018 average for Sarnia is derived from data from February to May, July, and October to December in 2018.
The 2018 average for Hamilton Downtown is derived from data from March to June, August, and October to December in 2018.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

Canadian Ambient Air Quality Standard reporting

PM_2.5 and ozone CAAQS metric values for designated sites across Ontario (2022)
Air zone area	City/Town	24-hour PM_2.5 (μg/m³)	Annual PM_2.5 (μg/m³)	8-hour ozone (ppb)
Sarnia	Sarnia	19	7.3	69*(42)
Hamilton	Hamilton Downtown	22	8.5	64*(49)
Hamilton	Hamilton Mountain	19	7.6	65*(50)
Sudbury	Sudbury	15	5.4	55(42)
Sault Ste. Marie	Sault Ste. Marie	13	4.9	62(43)
Northern Ontario	Thunder Bay	16	5.7	50(43)
Southern Ontario	Windsor Downtown	19	7.7	68*(42)
Southern Ontario	Chatham	17	6.8	65*(43)
Southern Ontario	London	18	7.1	64*(45)
Southern Ontario	Brantford	17	7.1	66*(51)
Southern Ontario	Kitchener	19	7.3	64*(46)
Southern Ontario	Guelph	19	7.1	67*(48)
Southern Ontario	St. Catharines	16	6.1	65*(49)
Southern Ontario	Burlington	17	6.7	64*(53)
Southern Ontario	Oakville	17	6.7	66*(55)
Southern Ontario	Milton	19	7.2	65*(51)
Southern Ontario	Mississauga	18	7.2	63*(52)
Southern Ontario	Brampton	18	7.0	67*(51)
Southern Ontario	Toronto West	17	7.1	63*(51)
Southern Ontario	Toronto Downtown	20	8.0	63*(51)
Southern Ontario	Toronto North	19	6.9	67*(51)
Southern Ontario	Toronto East	19	6.9	63*(47)
Southern Ontario	Oshawa	17	6.0	64*(44)
Southern Ontario	Barrie	18	6.7	60(44)
Southern Ontario	Peterborough	18	6.2	62(46)
Southern Ontario	Kingston	15	5.8	66*(46)
Southern Ontario	Ottawa Downtown	17	6.1	58(47)

Note:

Designated sites normally refer to communities with populations greater than 100,000.
The CAAQS for 24h PM_2.5 is 27 μg/m³ based on the 98^th percentile measurement annually, averaged over three consecutive years.
The CAAQS for annual PM_2.5 is 8.8 μg/m³ based on the annual average of the daily 24-hour average concentrations averaged over three consecutive years.
The CAAQS for ozone is 62 ppb based on the consecutive three-year average of the annual 4^th highest daily maximum eight-hour running average.
An asterisk denotes an exceedance of the CAAQS.
Value in parenthesis is the calculated 8h ozone CAAQS metric once the transboundary influence was removed.

NO₂ and SO₂ CAAQS metric values for designated sites across Ontario (2022)
Air zone area	City/Town	1-hour NO₂ (ppb)	Annual NO₂ (ppb)	1-hour SO₂ (ppb)	Annual SO₂ (ppb)
Sarnia	Sarnia	36	6.7	68	2.5
Hamilton	Hamilton Downtown	44	10.6	81*	3.7
Hamilton	Hamilton Mountain	36	6.1	63	3.1
Sudbury	Sudbury	45	6.1	45	1.1
Sault Ste. Marie	Sault Ste. Marie	29	3.8	26	0.8
Northern Ontario	Thunder Bay	43	7.0	N/A	N/A
Southern Ontario	Windsor Downtown	42	9.4	14	0.4
Southern Ontario	Chatham	28	4.5	N/A	N/A
Southern Ontario	London	28	4.9	N/A	N/A
Southern Ontario	Brantford	25	5.0	N/A	N/A
Southern Ontario	Kitchener	35	5.4	N/A	N/A
Southern Ontario	Guelph	34	5.1	N/A	N/A
Southern Ontario	St. Catharines	33	5.7	N/A	N/A
Southern Ontario	Burlington	40	8.5	N/A	N/A
Southern Ontario	Oakville	39	7.8	N/A	N/A
Southern Ontario	Milton	43	8.3	INS	INS
Southern Ontario	Mississauga	37	7.5	N/A	N/A
Southern Ontario	Brampton	42	7.2	N/A	N/A
Southern Ontario	Toronto West	48	13.2	7	0.3
Southern Ontario	Toronto Downtown	52	14.4	N/A	N/A
Southern Ontario	Toronto North	44	10.2	6	0.2
Southern Ontario	Toronto East	45	9.9	N/A	N/A
Southern Ontario	Oshawa	22	3.7	N/A	N/A
Southern Ontario	Barrie	40	5.8	N/A	N/A
Southern Ontario	Peterborough	36	4.5	N/A	N/A
Southern Ontario	Kingston	32	3.5	N/A	N/A
Southern Ontario	Ottawa Downtown	40	6.1	2	0.3

Note:

Designated sites normally refer to communities with populations greater than 100,000.
The CAAQS for 1h NO₂ is 60 ppb is based on the 3-year average of the annual 98^th percentile of the daily maximum 1-hour average NO₂ concentrations.
The CAAQS for annual NO₂ is 17.0 ppb based on the average over a single calendar year of all the 1h average NO₂ concentrations.
The CAAQS for 1h SO₂ is 70 ppb based on the 3-year average of the annual 99^th percentile of the SO₂ daily maximum 1-hour average concentrations.
The CAAQS for annual SO₂ is 5.0 ppb based on the average over a single calendar year of all 1h average SO₂ concentrations.
An asterisk denotes an exceedance of the CAAQS.
INS denotes insufficient data to report a valid CAAQS metric.
N/A denotes not applicable (parameter not monitored at location).

PM_2.5 and ozone CAAQS metric trends for designated sites across Ontario (2013-2022)
Air zone area	City/Town	10-year trend (%) based on 24-hour PM_2.5	10-year trend (%) based on annual PM_2.5	10-year trend (%) based on 8-hour ozone
Sarnia	Sarnia	-19.8	-34.4	N-SSS
Hamilton	Hamilton Downtown	-24.9	-19.0	N-SSS
Hamilton	Hamilton Mountain	-16.2	-15.5	-7.6
Sudbury	Sudbury	N-SSS	N-SSS	-13.8
Sault Ste. Marie	Sault Ste. Marie	-15.3	-17.6	N-SSS
Northern Ontario	Thunder Bay	N-SSS	N-SSS	-8.2
Southern Ontario	Windsor Downtown	-16.4	-20.5	-7.8
Southern Ontario	Chatham	N-SSS	N-SSS	-12.2
Southern Ontario	London	-20.7	-23.9	-12.7
Southern Ontario	Brantford	-20.9	-17.5	-12.5
Southern Ontario	Kitchener	-16.4	-17.0	-8.8
Southern Ontario	Guelph	N-SSS	-11.4	-6.4
Southern Ontario	St. Catharines	-15.7	-27.8	N-SSS
Southern Ontario	Burlington	-27.7	-26.2	-5.7
Southern Ontario	Oakville	-20.9	-17.8	N-SSS
Southern Ontario	Milton	-10.7	-15.9	-7.6
Southern Ontario	Mississauga	-20.2	-12.7	-8.1
Southern Ontario	Brampton	-20.0	-15.1	N-SSS
Southern Ontario	Toronto West	-20.7	-20.5	-8.2
Southern Ontario	Toronto Downtown	INS	INS	INS
Southern Ontario	Toronto North	-25.2	-28.1	N-SSS
Southern Ontario	Toronto East	N-SSS	-18.9	N-SSS
Southern Ontario	Oshawa	N-SSS	-20.7	N-SSS
Southern Ontario	Barrie	N-SSS	N-SSS	-8.3
Southern Ontario	Peterborough	N-SSS	-16.3	-11.2
Southern Ontario	Kingston	N-SSS	-26.1	N-SSS
Southern Ontario	Ottawa Downtown	-19.3	N-SSS	N-SSS

Notes:

Designated sites normally refer to communities with populations greater than 100,000.
N-SSS denotes Non-Significant Sen’s Slope (significant trend not detected).
INS denotes insufficient data for a valid 10-year trend.

NO₂ and SO₂ CAAQS metric trends for designated sites across Ontario (2013-2022)
Air zone area	City/Town	10-year trend (%) based on 1-hour NO₂	10-year trend (%) based on annual NO₂	10-year trend (%) based on 1-hour SO₂	10-year trend (%) based on annual SO₂
Sarnia	Sarnia	N-SSS	-25.7	N-SSS	-30.0
Hamilton	Hamilton Downtown	-8.4	-19.5	N-SSS	-14.3
Hamilton	Hamilton Mountain	-16.4	-32.0	N-SSS	N-SSS
Sudbury	Sudbury	N-SSS	-20.5	-91.5	-64.8
Sault Ste. Marie	Sault Ste. Marie	-14.1	-24.6	-22.5	N-SSS
Northern Ontario	Thunder Bay	N-SSS	-13.8	N/A	N/A
Southern Ontario	Windsor Downtown	-18.4	-29.6	-80.7	-81.3
Southern Ontario	Chatham	-19.9	-26.1	N/A	N/A
Southern Ontario	London	-25.0	-28.2	N/A	N/A
Southern Ontario	Brantford	-21.1	-8.1	N/A	N/A
Southern Ontario	Kitchener	-15.0	-26.4	N/A	N/A
Southern Ontario	Guelph	-16.2	-27.7	N/A	N/A
Southern Ontario	St. Catharines	-19.7	-27.4	N/A	N/A
Southern Ontario	Burlington	-10.2	-25.9	N/A	N/A
Southern Ontario	Oakville	-13.0	-14.8	N/A	N/A
Southern Ontario	Milton	N-SSS	N-SSS	INS	INS
Southern Ontario	Mississauga	-16.7	-26.7	N/A	N/A
Southern Ontario	Brampton	-15.0	-39.0	N/A	N/A
Southern Ontario	Toronto West	-16.4	-25.4	-46.9	-79.0
Southern Ontario	Toronto Downtown	INS	INS	N/A	N/A
Southern Ontario	Toronto North	-12.0	-34.8	N/A	N/A
Southern Ontario	Toronto East	-11.7	-40.3	N/A	N/A
Southern Ontario	Oshawa	-39.0	-52.6	N/A	N/A
Southern Ontario	Barrie	N-SSS	-31.9	N/A	N/A
Southern Ontario	Peterborough	N-SSS	-21.2	N/A	N/A
Southern Ontario	Kingston	N-SSS	-15.5	N/A	N/A
Southern Ontario	Ottawa Downtown	N-SSS	-24.5	-90.0	N-SSS

Notes:

Designated sites normally refer to communities with populations greater than 100,000.
N-SSS denotes Non-Significant Sen’s Slope (significant trend not detected).
INS denotes insufficient data for a valid 10-year trend.
N/A denotes not applicable (parameter not monitored at location).

Management levels for CAAQS pollutants

Ozone
Management level	8-hour 2020
Red	> 62 ppb
Orange	57 to 62 ppb
Yellow	51 to 56 ppb
Green	≤ 50 ppb

Fine particulate matter (PM_2.5)
Management level	24-hour 2020	Annual 2020
Red	> 27 µg/m³	> 8.8 µg/m³
Orange	20 to 27 µg/m³	6.5 to 8.8 µg/m³
Yellow	11 to 19 µg/m³	4.1 to 6.4 µg/m³
Green	≤ 10 µg/m³	≤ 4.0 µg/m³

Sulphur dioxide (SO₂)
Management level	1-hour 2020	Annual 2020
Red	> 70 ppb	> 5.0 ppb
Orange	51 to 70 ppb	3.1 to 5.0 ppb
Yellow	31 to 50 ppb	2.1 to 3.0 ppb
Green	≤ 30 ppb	≤ 2.0 ppb

Nitrogen dioxide (NO₂)
Management level	1-hour 2020	Annual 2020
Red	> 60 ppb	> 17.0 ppb
Orange	32 to 60 ppb	7.1 to 17.0 ppb
Yellow	21 to 30 ppb	2.1 to 7.0 ppb
Green	≤ 20 ppb	≤ 2.0 ppb

Air quality management actions by air zone area

Ontario air quality management actions across all air zones
Type	Action	Description
Air permissions and approvals	Air Emissions Environmental Activity and Sector Registry	Businesses that engage in certain routine activities that generate air emissions must self-register online in the Environmental Activity and Sector Registry (EASR). They must submit information about their emissions to the MECP and follow standardized rules set out in guidance materials. A business may also be inspected to ensure conditions are met.
Air permissions and approvals	Environmental Compliance Approvals	Businesses with complex or unique types of operations must apply for an Environmental Compliance Approval (ECA). By law, a business must meet the specific conditions set out in the ECA. A business may also be inspected to ensure conditions are met.
Regulations	Regulation 419/05: Air Pollution - Local Air Quality	This regulation establishes air health or environmental-based standards that apply to industrial and commercial facilities. Facilities can comply with O. Reg. 419/05 in one of three ways. First, meeting the air standards set out in the regulation is the default compliance approach. For facilities that are technically and/or economically unable to meet the air standards, two additional options are available: requesting, obtaining and complying with a site-specific standard for an individual facility; or registering to a technical or industry standard, if an applicable standard is available for the sector.
Regulations	Regulation 271/91: Gasoline Volatility	O. Reg. 271/91 specifies upper limits for gasoline volatility in southern and northern Ontario for the summer driving season and requires petroleum facilities to track and report gasoline volatility limits during this period.
Regulations	O. Reg. 455/94: Recovery of Gasoline Vapour in Bulk Transfers	O. Reg. 455/94 reduces the discharge of gasoline vapour into the natural environment from terminals, bulk plants or service stations.
Ambient air standards	Ambient Air Quality Criteria (AAQC)	The AAQCs set out air contaminant concentrations that are protective against adverse effects on health and/or the environment. AAQCs are used to assess general (ambient) air quality resulting from all sources of a contaminant to air.
Ambient air standards	Canadian Ambient Air Quality Standards (CAAQS)	The CAAQS are national ambient air quality objectives set out by the Canadian Council of Ministers of the Environment (CCME), in collaboration with provinces and territories, for nitrogen dioxide (NO₂), sulphur dioxide (SO₂), fine particulate matter (PM_2.5) and ozone (O₃).
Monitoring	Provincial Air Monitoring Network	Ontario operates a network of 38 ambient (outside) air monitoring stations across the province that collect real-time air pollution data.
Monitoring	Air Quality Health Index (AQHI)	The AQHI evaluates air monitoring information and issues hourly forecasts to help you understand what the quality of the air around you means to your health.
Community engagement	Air Standards/Local Air Quality External Working Group	Ministry led facilitated discussions with industry, public health groups, environmental non-government organizations and some First Nations on matters relating to the local air quality regulation (O. Reg. 419/05).

Ontario air quality management actions by air zone

Northern Ontario (excluding Sault Ste. Marie and Sudbury)

CAAQS management levels

PM_2.5: yellow
Ozone: green
SO₂: nil (no monitoring station in air zone)
NO₂: orange

Type	Action	Description
Industry standard registrations	Forest products industry standard	Imposes requirements on registered forest product facilities (e.g., sawmills) to reduce emissions of acrolein and other contaminants that can contribute to the development of PM_2.5. As of 2022, 13 facilities were registered in the Northern Ontario air zone.
Industry standard registrations	Pulp and paper industry standard	Imposes requirements on registered pulp and paper facilities to reduce emissions of total reduced sulphur, acrolein and other contaminants which can contribute to the development of PM_2.5. As of 2022, 4 facilities were registered in the Northern Ontario air zone.

Southern Ontario (excluding Sarnia/St. Clair Township and Hamilton)

CAAQS management levels

PM_2.5: orange
Ozone: yellow
SO₂: green
NO₂: orange

Type	Action	Description
Regulations	O. Reg. 88/22 Air Pollution – Discharge of Sulphur Dioxide from Petroleum Facilities	Came into effect on February 25, 2022. Imposes requirements on specified petroleum facilities to address sulphur dioxide air emissions with new requirements starting in 2024 to 2029. Two of the specified facilities are in the southern air zone – Imperial Oil Limited (Nanticoke) and PCLI (Mississauga).
Regulations	O. Reg. 530/18: Air Pollution – Discharge of Sulphur Dioxide from Petroleum Facilities	Improves how acid gas flaring events are managed and strengthens accountability through reporting, monitoring and environmental penalties. It applies to specific facilities, including two facilities in the southern air zone – Imperial Oil Limited (Nanticoke) and PCLI (Mississauga).
Regulations	O. Reg. 222/07 Environmental Penalties	Enables environmental penalties to be levied from petroleum facilities that are in contravention of requirements under O. Reg. 530/18 and 88/22.
Industry standard registrations	Metal finishers industry standard	Imposes requirements on registered metal finishing facilities to reduce emissions of various contaminants including hexavalent chromium. As of 2022, 8 facilities were registered in the Southern Ontario air zone.
Industry standard registrations	Foundries industry standard	Imposes requirements on registered foundries (e.g., metal works facilities) to reduce emissions of various contaminants including SO₂ and NO₂. As of 2022, 16 facilities were registered in the Southern Ontario air zone.
Industry standard registrations	Petroleum refining industry standard	Requirements related to sources of benzene and benzo[a]pyrene from storage vessels, equipment leaks, sewage treatment operations and truck and railcar product loading racks and marine vessel loading berths. As of 2022, 1 facility was registered in the Southern Ontario air zone.
Site-specific standards	ADM Agri-Industries Company in Windsor	Requires action to reduce emissions of, and sets an alternative air standard for, suspended particulate matter emissions at a grain handling and oilseed processing facility. This site-specific standard was issued in December 2018 and expires in 2028.
Site-specific standards	Stelco Lake Erie Works in Nanticoke	Requires action to reduce emissions of and sets an alternative air standard for suspended particulate matter, benzene and benzo[a]pyrene. These site-specific standards were issued in March 2015 and May 2016 and all will expire in 2023.
Site-specific standards	Harsco Canada Corp in Nanticoke	Requires action to reduce emissions of, and sets an alternative air standard for, suspended particulate matter emissions at a slag processing operation located on site at Stelco’s Lake Erie Works facility in Nanticoke. This site-specific standard was issued in March 2015 and expires in 2023.
Site-specific standards	Owens Corning Composite Materials Canada LP in Guelph	Requires action to reduce emissions of, and sets an alternative air standard for, hexavalent chromium. This site-specific standard was issued in July 2016 and will expire in 2026.
Site-specific standards	Oxy Vinyls Canada Co. in Thorold	Requires action to reduce emissions of, and sets an alternative air standard for, vinyl chloride air emissions This site-specific standard was issued in February 2017 and will expire in 2027.

Sudbury

CAAQS management levels

PM_2.5: yellow
Ozone: green
SO₂: yellow
NO₂: orange

Type	Action	Description
Regulations	O. Reg. 652/21: Air Pollution - Discharge of Sulphur Dioxide from Nickel Smelting and Refining Facilities in the Sudbury Area	Came into effect on January 1, 2022. Imposes requirements on the nickel smelting and refining industry in the Sudbury area to address sulphur dioxide air emissions.
Industry standard registrations	Metal finishers industry standard	Imposes requirements on registered metal finishing facilities to reduce emissions of various contaminants including hexavalent chromium. As of 2022, 1 facility was registered in the Sudbury air zone.
Site-specific standards	Glencore Canada Corporation	Requires action to reduce emissions of, and sets an alternative air standards for, cadmium, nickel and nickel compounds. These site-specific standards were issued between 2015 and 2020 and expire between 2020 and 2030.
Site-specific standards	Vale Canada Ltd.	Requires action to reduce emissions of, and sets an alternative air standard for, nickel and nickel compounds. This site-specific standard was issued in December 2021 and will expire in 2030.

Sault Ste. Marie

CAAQS management levels

PM_2.5: yellow
Ozone: green
SO₂: green
NO₂: yellow

Type	Action	Description
Industry standard registrations	Forest products industry standard	Imposes requirements on registered forest product facilities (e.g., sawmills) to reduce emissions of acrolein and other contaminants that can contribute to the development of PM_2.5. As of 2022, 1 facility was registered in the Sault Ste. Marie air zone.
Site-specific standards	Algoma Steel Inc.	Requires action to reduce emissions of, and sets an alternative air standards for, benzene, benzo[a]pyrene and suspended particulate matter. The site-specific standard for benzo[a]pyrene, issued in 2017, expired in November 2022. These site-specific standards were issued between 2015 and 2017 and expire between 2022 and 2023.
Financial Support for Clean Steelmaking	Algoma Steel Inc.	Ontario is providing financial support to this facility (as well as ArcelorMittal Dofasco in Hamilton) as it transitions away from the use of coal to clean steelmaking that is expected to reduce air pollutants in addition to greenhouse gas emissions.

Sarnia/St. Clair Township

CAAQS management levels

PM_2.5: orange
Ozone: green
SO₂: orange
NO₂: orange

Type	Action	Description
Regulations	O. Reg. 88/22: Air Pollution – Discharge of Sulphur Dioxide from Petroleum Facilities	Came into effect on February 25, 2022. Imposes requirements on specified petroleum facilities to address sulphur dioxide air emissions with new requirements starting in 2024 to 2029. Three of the specified facilities are in the Sarnia/St. Clair Township air zone.
Regulations	O. Reg. 530/18: Air Pollution – Discharge of Sulphur Dioxide from Petroleum Facilities	Improves how acid gas flaring events are managed and strengthens accountability through reporting, monitoring and environmental penalties. Three facilities in the Sarnia/St. Clair Township air zone.
Regulations	O. Reg. 222/07 Environmental Penalties	Enables environmental penalties to be levied from petroleum facilities that are in contravention of requirements under O. Reg. 530/18 and 88/22.
Regulations	Regulation 350 - Lambton Industry Meteorological Alert (LIMA)	Public alerts are issued if the running daily (24-hr) average sulphur dioxide concentration reaches 0.07 parts per million at any of the monitoring stations in the LIMA network.
Policy	Cumulative effects assessment in air approvals	Guides decisions on Environmental Compliance Approval (ECA) applications for new or expanding facilities with emissions of benzene (in Sarnia and Hamilton) and/or benzo[a]pyrene (Hamilton only).
Industry standard registrations	Petroleum refining industry standard	Requirements related to sources of benzene and benzo[a]pyrene from storage vessels, equipment leaks, sewage treatment operations and truck and railcar product loading racks and marine vessel loading berths. As of 2022, 3 facilities were registered in the Sarnia/St. Clair Township air zone.
Industry standard registrations	Petrochemical industrial standard	Requirements related to sources of benzene and 1,3-butadiene from storage vessels, equipment leaks, sewage treatment operations and truck and railcar product loading racks and marine vessel loading berths. As of 2022, 4 facilities were registered in the Sarnia/St. Clair Township air zone.
Enhanced monitoring	Property line monitoring, petroleum refining and petrochemical industries	Facilities registered to the Petroleum Refining and Petrochemical Industry Standards are required to monitor benzene or 1,3-butadiene levels at their fence lines (known as “property line monitoring”) and provide the results on a public website within 60 days.
Enhanced monitoring	Clean Air Sarnia and Area (CASA) Air Monitoring Network	This monitoring network includes 9 ambient air monitoring stations operated by the Bluewater Association for Safety, Environment, and Sustainability (BASES) (previously known as the Sarnia Lambton Environmental Association), an industrial cooperative of 18 facilities operating in Lambton County as well as one provincial MECP AQHI stations and four local MECP-operated stations.
Enhanced community engagement	Sarnia Area Environmental Health Project	This project assesses the impact of air exposures and other stressors in the Sarnia Area on human health.
Enhanced community engagement	Clean Air Sarnia Area (CASA)	Community advisory panel is made up of representatives from the public, government, First Nations, and industry, who are dedicated to providing the community with a clear understanding of ambient air quality in the Sarnia area. Roles include information sharing, identifying and researching local air quality issues, provide info and recommendations to MECP and Sarnia-Lambton Environmental Association, informing public of local air quality, also maintenance of public CASA website which contains air monitoring data from SLEA and MECP as well as 1 AQHI station.

Hamilton

CAAQS management levels

PM_2.5: orange
Ozone: green
SO₂: red
NO₂: orange

Type	Action	Description
Policy	Cumulative effects assessment in air approvals	Guides decisions on Environmental Compliance Approval (ECA) applications for new or expanding facilities with emissions of benzene (in Sarnia and Hamilton) and/or benzo[a]pyrene (Hamilton only).
Policy	Local Poor Air Quality Notification Protocol	The Local Poor Air Quality Notification (LPAQN) protocol is a program through which companies are asked to voluntarily implement operational practices and control measures to reduce releases of dust and particulate matter to air during poor air quality events. The protocol addresses poor air quality events that are the result of unique conditions in Hamilton that are conducive to the build-up of pollutants in the lower part of the City. Approximately 33 industries and municipal operations participate and enact poor air quality plans when a Notification is issued in response to defined considerations.
Industry standard registrations	Foundries industry standard	Imposes requirements on registered foundries (e.g., metal works facilities) to reduce emissions of various contaminants including metals, VOCs, suspended particulate matter, SO₂ and NO₂. As of 2022, 1 facility was registered in the Hamilton air zone.
Site-specific standards	Stelco	Requires action to reduce emissions of, and sets an alternative air standards for, benzene, benzo[a]pyrene, and suspended particulate matter. These site-specific standards were issued in 2015 and 2016 and expire in 2023.
Site-specific standards	ArcelorMittal Dofasco	Requires action to reduce emissions of, and sets an alternative air standards for, benzene, benzo(a)pyrene, manganese and manganese compounds, and total suspended particulate matter. These site-specific standards were issued in 2015 and 2016 and expire in 2023.
Site-specific standards	Harsco Canada Corp	Requires action to reduce emissions of, and sets an alternative air standard for, suspended particulate matter and manganese and manganese compound emissions at a slag processing operation located on site at the ArcelorMittal Dofasco facility in Hamilton. These site-specific standards were issued in May 2016 and expires in 2023.
Site-specific standards	Rain Carbon (formerly Ruetgers Canada Inc.)	Requires action to reduce emissions of, and sets alternative air standards for, benzene and benzo(a)pyrene. These site-specific standards were issued in 2017 and expire in 2022.
Site-specific standards	Carmeuse Lime (Canada) Limited	Requires action to reduce emissions of, and sets alternative air standards for, calcium oxide and suspended particulate matter. These site-specific standards were issued in 2018 and expire in 2028.
Enhanced monitoring	Hamilton Air Monitoring Network (HAMN)	A comprehensive air monitoring network, made up of industry-operated and ministry-operated stations that measure impacts from industrial operations and is used to assess ambient air conditions in Hamilton. The ministry conducts regular audits of industry station in the network since 2003. HAMN provides the ministry with real-time air quality alerts based on agreed thresholds as well as monthly exceedance reports and quarterly and annual summary reports.
Enhanced community engagement	Clean Air Hamilton	Clean Air Hamilton is a multi-stakeholder, member-based organization dedicated to improving air quality in Hamilton. The ministry has been a long-standing member of Clean Air Hamilton for over 20 years. Staff from the ministry’s West Central Region participate in monthly Clean Air Hamilton meetings to discuss updates on local air quality initiatives and activities and respond to questions regarding ministry air quality related activities in Hamilton. The ministry provides supporting information for the Clean Air Hamilton annual progress report.
Financial Support for Clean Steelmaking	ArcelorMittal Dofasco	Ontario is providing financial support for this facility (as well as Algoma Steel in Sault Ste. Marie) as it transitions away from the use of coal to clean steelmaking that is expected to reduce air pollutants in addition to greenhouse gas emissions.

Changes in air quality management actions since 2022

Approvals/programs/regulations that have since ended
Air zone	Program/Regulation	Description
Northern Ontario	Pulp and Paper Industry Standard	Imposes requirements on registered pulp and paper facilities to reduce emissions of total reduced sulphur, acrolein and other contaminants which can contribute to the development of PM_2.5. In 2024 Domtar Espanola was deregistered at the company’s request due to the facility ceasing operations. This brings the total number of registered facilities in the Northern Ontario Air Zone to 3.
Sarnia/St. Clair Township	Sarnia Area Environmental Health Project	Final reports of findings from the Sarnia Area Environmental Health Project were posted to the CASA website in March 2024.

New actions since 2022
Air zone	Program/Regulation	Description
Northern Ontario	Foundries industry standard	Imposes requirements on registered foundries (e.g., metal works facilities) to reduce emissions of various contaminants including metals, VOCs, suspended particulate matter, SO₂ and NO₂. On January 12, 2023, a facility registered to this industry standard bringing the total number of registered facilities in the Northern Ontario Air Zone to one.
Southern Ontario	Metal finishers industry standard	Imposes requirements on registered metal finishing facilities to reduce emissions of various contaminants including hexavalent chromium. On March 12, 2024, an additional facility registered to this industry standard bringing the total number of registered facilities in the Southern Ontario Air Zone to 10.
Southern Ontario	OPG Lennox site-specific standards	On March 15, 2023, the MECP issued multiple site-specific standards requiring action to reduce emissions of, and set an alternative air standard for, SO₂, NO_x, and sulfuric acid from natural gas/RFO electricity generation. These site-specific standards expire in 2033.
Southern Ontario	Asphalt mix industry standard	Requirements to control emissions of various compounds, including metals, particulate, and VOCs from asphalt mixing, storage, crushing, roads, and dryers/oil burners and generators. Between January 2023 and July 2024, 4 companies registered to this industry standard bringing the total number of registered facilities in the Southern Ontario Air Zone to 4.
Southern Ontario	Stelco Lake Erie Works	On July 1, 2023, the site-specific standards for Stelco Inc. expired. On the same day, updated general air standards for sulphur dioxide came into effect. Stelco Inc. is now out of compliance with O. Reg. 419/05 general air standards for benzene, benzo[a]pyrene, suspended particulate matter and sulphur dioxide. In accordance with the regulation, the facility has submitted notices of exceedance and a proposed abatement plan. The environmental compliance approvals for Stelco Inc. contains requirements to manage the emissions of the contaminants that had site-specific standards. The operations and environmental controls that were in place prior to the expiry of the site-specific standards remain in effect. The abatement plans in combination with the environmental compliance approvals will ensure accountability until a longer-term compliance pathway is determined. The ministry continues to inspect Stelco Hamilton and Lake Erie Works to assess compliance with air legislation, regulations and conditions in environmental approvals and orders.
Southern Ontario	Harsco Canada Corp Nanticoke	On July 1, 2023, the site-specific standards for Harsco expired. Harsco is now out of compliance with O. Reg. 419/05 general air standards for suspended particulate matter, manganese and manganese compounds. In accordance with the regulation, the facility has submitted notices of exceedance and a proposed abatement plan. The environmental compliance approvals for Harsco contains requirements to manage the emissions of the contaminants that had site-specific standards. The operations and environmental controls that were in place prior to the expiry of the site-specific standards remain in effect. The abatement plans in combination with the environmental compliance approvals will ensure accountability until a longer-term compliance pathway is determined. The ministry continues to inspect Harsco to assess compliance with air legislation, regulations and conditions in environmental approvals and orders.
Sault Ste. Marie	Algoma Steel Inc.	In November 2022 and July 2023, the site-specific standards for Algoma Steel Inc. expired. On July 1, 2023, updated general air standards for sulphur dioxide came into effect. In March 2023 Algoma Steel submitted applications for new site-specific standards, which are still under review by the ministry. As such, Algoma Steel is out of compliance with O. Reg. 419/05 general air standards for benzene, benzo[a]pyrene, suspended particulate matter and sulphur dioxide. In accordance with the regulation, the facility has submitted notices of exceedance and a proposed abatement plan. The environmental compliance approvals for Algoma Steel contain requirements to manage the emissions of the contaminants that had site-specific standards. The operations and environmental controls that were in place prior to the expiry of the site-specific standards remain in effect. The abatement plans in combination with the environmental compliance approvals will ensure accountability until a longer-term compliance pathway is determined. The ministry continues to inspect the facility to assess compliance with air legislation, regulations and conditions in environmental approvals and orders.
Hamilton	ArcelorMittal Dofasco	On July 1, 2023, the site-specific standards for ArcelorMittal Dofasco expired. On the same day, updated general air standards for sulphur dioxide came into effect. ArcelorMittal Dofasco is now out of compliance with O. Reg. 419/05 general air standards for benzene, benzo[a]pyrene, suspended particulate matter, manganese and manganese compounds and sulphur dioxide. In accordance with the regulation, the facility has submitted notices of exceedance and a proposed abatement plan. The environmental compliance approvals for ArcelorMittal Dofasco contains requirements to manage the emissions of the contaminants that had site-specific standards. The operations and environmental controls that were in place prior to the expiry of the site-specific standards remain in effect. The abatement plans in combination with the environmental compliance approvals will ensure accountability until a longer-term compliance pathway is determined. The ministry continues to inspect ArcelorMittal Dofasco to assess compliance with air legislation, regulations and conditions in environmental approvals and orders.
Hamilton	Stelco Hamilton	On July 1, 2023, the site-specific standards for Stelco Inc. expired. On the same day, updated general air standards for sulphur dioxide came into effect. Stelco Inc. is now out of compliance with O. Reg. 419/05 general air standards for benzene, benzo[a]pyrene, suspended particulate matter and sulphur dioxide. In accordance with the regulation, the facility has submitted notices of exceedance and a proposed abatement plan. The environmental compliance approvals for Stelco Inc. contains requirements to manage the emissions of the contaminants that had site-specific standards. The operations and environmental controls that were in place prior to the expiry of the site-specific standards remain in effect. The abatement plans in combination with the environmental compliance approvals will ensure accountability until a longer-term compliance pathway is determined. The ministry continues to inspect Stelco Hamilton and Lake Erie Works to assess compliance with air legislation, regulations and conditions in environmental approvals and orders.
Hamilton	Harsco Canada Corp Hamilton	On July 1, 2023, the site-specific standards for Harsco expired. Harsco is now out of compliance with O. Reg. 419/05 general air standards for suspended particulate matter, manganese and manganese compounds. In accordance with the regulation, the facility has submitted notices of exceedance and a proposed abatement plan. The environmental compliance approvals for Harsco contain requirements to manage the emissions of the contaminants that had site-specific standards. The operations and environmental controls that were in place prior to the expiry of the site-specific standards remain in effect. The abatement plans in combination with the environmental compliance approvals will ensure accountability until a longer-term compliance pathway is determined. The ministry continues to inspect Harsco to assess compliance with air legislation, regulations and conditions in environmental approvals and orders.
Hamilton	Rain Carbon (formerly Ruetgers Canada Inc.)	Rain Carbon’s site-specific standard expired on November 21, 2022. A request for new site-specific standards for Benzene and Benzo(a)pyrene and an application for an amended ECA was submitted to the ministry on May 1, 2023. Following a review by the ministry, revised documents were submitted on May 13, 2024, and these applications are currently under review. Now that these site-specific standards have expired, the general standards for benzene and benzo(a)pyrene within the local air quality regulation apply to the facility. Emission estimates and monthly air monitoring results submitted by Rain Carbon indicate that the company is exceeding these air standards.
Sarnia/St. Clair Township	O. Reg. 206/24: Air Pollution – Discharge of Benzene from INEOS Styrolution	This regulation came into effect on June 14, 2024. It imposes requirements on INEOS Styrolution in Sarnia to address benzene emissions, including new health-based benzene concentration limits and enhanced monitoring requirements.

AQHI and air quality alert program reporting

2022 Air Quality Health Index summary
Station ID	City/Town	No. of valid hours	Low risk AQHI=1	Low risk AQHI=2	Low risk AQHI=3	Moderate risk AQHI=4	Moderate risk AQHI=5	Moderate risk AQHI=6	High risk AQHI=7	High risk AQHI=9	Very high risk AQHI=+	No. of days at least 1 hour > 6
12008	Windsor Downtown	8584	2.20	36.31	48.24	11.39	1.71	0.07	0.07	0	0	3
12016	Windsor West	8644	2.13	44.92	41.96	9.86	1.10	0.02	0.01	0	0	1
13001	Chatham	8351	8.67	54.87	31.16	4.92	0.34	0.01	0.04	0	0	1
14111	Sarnia	8639	6.23	49.57	33.02	9.84	1.15	0.14	0.06	0	0	2
15020	Grand Bend	8151	13.85	61.85	20.73	3.19	0.29	0	0.09	0	0	3
15026	London	8596	11.59	53.22	31.01	3.93	0.20	0	0.05	0	0	1
16015	Port Stanley	8706	14.76	62.13	19.50	3.16	0.36	0.02	0.07	0	0	1
18007	Tiverton	8559	13.72	62.90	20.73	2.37	0.21	0	0.07	0	0	2
21005	Brantford	8638	13.39	52.23	29.84	4.17	0.29	0	0.07	0	0	1
26060	Kitchener	8555	11.44	52.06	30.99	4.93	0.51	0.06	0	0	0	0
27067	St. Catharines	8645	8.94	57.47	30.35	3.03	0.20	0	0.01	0	0	1
28028	Guelph	8441	9.64	50.81	33.48	5.89	0.15	0	0.02	0	0	1
29000	Hamilton Downtown	8637	4.75	42.29	39.15	11.15	2.39	0.24	0.03	0	0	1
29118	Hamilton West	8712	6.20	49.37	35.97	7.40	0.96	0.07	0.02	0	0	1
29214	Hamilton Mountain	8538	7.38	57.55	28.55	6.01	0.43	0.06	0.01	0	0	1
31129	Toronto Downtown	8727	2.21	31.73	48.60	14.19	2.84	0.31	0.13	0	0	3
33003	Toronto East	8657	5.87	50.40	36.38	6.31	1.02	0.03	0	0	0	0
34021	Toronto North	8645	7.72	49.51	34.09	7.61	0.97	0.08	0.02	0	0	1
35125	Toronto West	8620	3.12	45.23	42.82	7.84	0.92	0.07	0	0	0	0
44008	Burlington	8575	6.38	53.46	34.02	5.80	0.34	0.01	0	0	0	0
44017	Oakville	8566	6.69	50.13	35.55	7.26	0.34	0	0.04	0	0	1
44029	Milton	8629	5.37	51.37	36.19	6.41	0.63	0.02	0.01	0	0	1
45027	Oshawa	8676	24.11	56.75	17.61	1.48	0.02	0.02	0	0	0	0
46090	Brampton	8693	8.96	54.16	29.99	6.28	0.48	0.03	0.02	0.01	0.06	2
46108	Mississauga	8661	8.53	56.91	29.79	4.30	0.39	0.08	0	0	0	0
47045	Barrie	8353	17.00	58.13	21.63	3.15	0.08	0	0	0	0	0
48006	Newmarket	8638	13.76	54.14	27.08	4.64	0.32	0.02	0.02	0	0	1
49005	Parry Sound	8502	23.44	57.09	17.83	1.63	0	0	0	0	0	0
49010	Dorset	8684	28.34	57.92	13.06	0.68	0	0	0	0	0	0
51001	Ottawa Downtown	8657	17.40	54.89	24.62	2.97	0.13	0	0	0	0	0
52023	Kingston	8718	14.19	63.06	21.29	1.39	0.07	0	0	0	0	0
54012	Belleville	8744	12.51	60.09	24.85	2.31	0.15	0.01	0.08	0	0	2
56051	Cornwall	8723	18.69	56.51	22.15	2.54	0.10	0.01	0	0	0	0
59006	Peterborough	8598	17.64	57.27	21.57	3.12	0.37	0.02	0	0	0	0
63203	Thunder Bay	8315	18.34	55.17	23.81	2.50	0.18	0	0	0	0	0
71078	Sault Ste. Marie	8728	20.96	56.93	20.46	1.62	0.03	0	0	0	0	0
75010	North Bay	8655	21.64	57.84	19.04	1.46	0.02	0	0	0	0	0
77233	Sudbury	8707	18.34	58.16	19.81	3.39	0.30	0	0	0	0	0

2022 air quality alert summary
Air quality forecast region	Special air quality statement	Smog and air health advisory
Algonquin	0	0
Atikokan - Upsala - Quetico	0	0
Attawapiskat	0	0
Bancroft - Bon Echo Park	0	0
Barrie - Orillia - Midland	0	0
Belleville - Quinte - Northumberland	1	0
Big Trout Lake - Sachigo Lake	0	0
Brockville - Leeds and Grenville	0	0
Burk's Falls - Bayfield Inlet	0	0
Chapleau - Gogama	0	0
City of Hamilton	2	0
City of Ottawa	0	0
City of Thunder Bay	0	0
City of Toronto	3	0
Cornwall - Morrisburg	0	0
Dryden - Ignace	0	0
Dufferin - Innisfil	1	0
Dunnville - Caledonia - Haldimand	1	0
Elgin	2	0
Elliot Lake - Ranger Lake	0	0
Fort Frances - Rainy Lake	0	0
Fort Hope - Webequie	0	0
Fort Severn	0	0
Geraldton - Manitouwadge - Hornepayne	0	0
Greater Sudbury and Vicinity	0	0
Grey - Bruce	2	0
Haliburton	0	0
Halton - Peel	3	0
Huron - Perth	3	0
Kapuskasing - Hearst	0	0
Kenora - Nestor Falls	0	0
Kingston - Prince Edward	0	0
Kirkland Lake - New Liskeard - Temagami	0	0
Lake Nipigon - Wabakimi	0	0
London - Middlesex	1	0
Manitoulin - Northshore - Killarney	0	0
Moosonee - Fort Albany	0	0
Niagara	1	0
Nipigon - Marathon - Superior North	0	0
North Bay - West Nipissing	0	0
Oxford - Brant	1	0
Parry Sound - Muskoka	0	0
Peawanuck	0	0
Peterborough - Kawartha Lakes	1	0
Pickle Lake - Wunnummin Lake	0	0
Prescott and Russell	0	0
Red Lake - Ear Falls	0	0
Renfrew - Pembroke - Barry's Bay	0	0
Sandy Lake - Pikangikum	0	0
Sarnia - Lambton	3	0
Sault Ste. Marie - Superior East	0	0
Simcoe - Delhi - Norfolk	1	0
Sioux Lookout - Savant Lake	0	0
Smiths Falls - Lanark - Sharbot Lake	0	0
Stirling - Tweed - South Frontenac	0	0
Superior West	0	0
Timmins - Cochrane	0	0
Waterloo - Wellington	2	0
Wawa - White River - Pukaskwa	0	0
Windsor - Essex - Chatham - Kent	3	0
York - Durham	3	0
Ontario	4	0

Roadside air monitoring in Ontario

2022 nitrogen dioxide (NO₂) annual statistics

Unit: parts per billion (ppb)
NO₂ 1h AAQC: 200 ppb
NO₂ 24h AAQC: 100 ppb

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
12008	Windsor Downtown	467 University Ave. W.	8689	3.4	5.2	7.3	10.2	17.7	38.5	9.4	60.3	28.3
12016	Windsor West	College Ave./South St.	8645	2.4	4.0	5.9	8.7	16.3	36.0	8.0	51.5	26.1
29000	Hamilton Downtown	Elgin St./Kelly St.	8610	3.2	5.0	7.5	12.0	23.2	39.9	10.6	57.0	35.7
29214	Hamilton Mountain	250 Fennell Ave. W.	8695	1.7	2.6	4.0	6.6	13.7	26.4	6.1	43.7	24.0
31129	Toronto Downtown	55 John St.	8583	6.2	9.2	12.2	16.3	25.9	43.8	14.4	75.6	35.1
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	8681	3.1	5.2	7.5	11.0	20.3	38.6	9.9	63.7	32.6
34021	Toronto North	4905 Dufferin St., ECCC	8727	2.9	5.0	7.7	12.0	20.9	39.8	10.2	59.0	32.2
35033	Etobicoke South	185 Judson St.	8529	4.3	7.4	10.9	16.2	27.1	44.4	13.7	71.6	34.6
35125	Toronto West	125 Resources Rd.	8604	4.2	7.5	10.8	15.8	26.0	41.1	13.2	57.8	33.3
63203	Thunder Bay	421 James St. S.	8718	1.3	2.6	4.3	7.3	16.5	36.9	7.0	55.6	35.4
75010	North Bay	Chippewa St. W., Dept. National Defence	8709	0.8	1.4	2.2	3.9	9.4	27.9	4.1	40.7	20.5
83126	Toronto Hwy 401	125 Resources Road, Hwy 401	8720	5.7	10.5	16.2	22.3	32.7	46.7	17.8	61.4	40.4
83133	Toronto Island	535 Lakeshore Ave., Toronto Island	8644	2.2	3.4	4.7	6.9	13.6	31.1	6.6	54.7	30.3

2022 fine particulate matter (PM_2.5) annual statistics

Unit: micrograms per cubic meter (µg/m³)
PM_2.5 24h reference level: 27 µg/m³
PM_2.5 Annual reference level: 8.8 µg/m³

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h	Number of times above reference level 24h	Number of times above reference level 1y
12008	Windsor Downtown	467 University Ave. W.	8743	2	4	6	9	15	28	7.83	55	26.2	0	0
12016	Windsor West	College Ave./South St.	8705	3	5	8	10	16	29	8.82	47	31.1	1	1
29000	Hamilton Downtown	Elgin St./Kelly St.	8645	2	4	7	11	18	33	8.64	90	34.8	3	0
29214	Hamilton Mountain	250 Fennell Ave. W.	8567	2	4	6	9	16	30	7.71	88	35.3	2	0
31129	Toronto Downtown	55 John St.	8729	2	5	7	9	15	29	7.92	50	30.6	2	0
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	8686	1	4	6	8	13	26	6.70	83	30.0	1	0
34021	Toronto North	4905 Dufferin St., ECCC	8656	2	4	6	8	13	26	6.79	50	33.0	1	0
35033	Etobicoke South	185 Judson St.	8296	2	4	6	9	15	27	7.73	48	28.5	1	0
35125	Toronto West	125 Resources Rd.	8670	2	4	6	8	13	24	6.90	58	28.4	1	0
63203	Thunder Bay	421 James St. S.	8748	2	3	4	6	9	15	5.03	30	17.5	0	0
75010	North Bay	Chippewa St. W., Dept. National Defence	8691	2	3	4	6	10	18	5.06	34	15.8	0	0
83126	Toronto Hwy 401	125 Resources Road, Hwy 401	8507	2	5	8	11	17	33	9.09	86	39.4	2	1
83133	Toronto Island	535 Lakeshore Ave., Toronto Island	8457	1	2	4	7	13	25	5.79	51	30.3	1	0

Notes:
Ontario uses the 24-hour PM_2.5 CAAQS “as is” for comparison to the 24-hour measurement of air quality data; this value is considered a Reference Level.
Ontario uses the annual PM_2.5 CAAQS “as is” for comparison to a single annual average of air quality data; this value is considered a Reference Level.

2022 ultrafine particles annual statistics

Unit: particles per cubic centimetre (#/cm³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
34021	Toronto North	4905 Dufferin St., ECCC	8424	3,325	6,285	9,213	12,670	19,747	35,892	10,696.6	94,040	24,705
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	8597	9,537	18,157	31,215	50,102	85,891	156,002	40,806.4	236,400	145,390
83133	Toronto Island	535 Lakeshore Ave., Hanlan's Point	4804	2,369	3,923	5,806	8,567	14,537	31,540	7,555.3	65,460	25,736

2022 black carbon annual statistics

Unit: micrograms per cubic metre (µg/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
12008	Windsor Downtown	467 University Ave. W.	8350	0.13	0.21	0.31	0.45	0.76	1.82	0.40	4.79	2.04
12016	Windsor West	College Ave./South St.	8416	0.14	0.23	0.33	0.48	0.82	1.93	0.44	5.45	1.95
29000	Hamilton Downtown	Elgin St./Kelly St.	6114	0.12	0.23	0.36	0.55	1.12	2.23	0.51	3.52	2.18
33003	Toronto East	Kennedy Rd./Lawrence Ave. E.	8636	0.12	0.20	0.30	0.44	0.76	1.53	0.39	5.84	1.35
34021	Toronto North	4905 Dufferin St., ECCC	8702	0.10	0.19	0.30	0.49	0.89	1.89	0.42	4.89	1.97
35033	Etobicoke South	185 Judson St.	8485	0.19	0.32	0.47	0.67	1.17	2.63	0.61	6.10	1.88
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	8740	0.26	0.48	0.76	1.25	2.22	4.09	1.05	6.48	3.10
83133	Toronto Island	535 Lakeshore Ave., Hanlan's Point	8649	0.00	0.11	0.20	0.34	0.67	1.57	0.29	4.16	1.21

2022 iron in PM_2.5 annual statistics

Unit: nanograms per cubic metre (ng/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
29000	Hamilton Downtown	Elgin St./Kelly St.	4714	13	29	47	80	242	1016	108.6	4909.5	737.0
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	7427	44	95	182	340	641	1304	280.8	5874.0	1020.6

2022 copper in PM_2.5 annual statistics

Unit: nanograms per cubic metre (ng/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
29000	Hamilton Downtown	Elgin St./Kelly St.	4714	1.2	1.6	2.1	3.2	9.0	38.6	4.5	216.7	36.6
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	7427	2.4	3.7	5.9	10.1	17.0	32.7	8.5	603.7	45.6

2022 manganese in PM_2.5 annual statistics

Unit: nanograms per cubic metre (ng/m³)
Mn in PM_2.5 24h AAQC: 0.1 µg/m³ (100 ng/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h	Number of times above 24h criteria
29000	Hamilton Downtown	Elgin St./Kelly St.	4714	0.0	0.3	0.7	1.6	7.7	45.8	3.5	608.0	41.2	0
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	7427	0.8	1.6	2.7	4.2	7.7	17.7	3.8	94.3	14.1	0

2022 lead in PM_2.5 annual statistics

Unit: nanograms per cubic metre (ng/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
29000	Hamilton Downtown	Elgin St./Kelly St.	4714	0.6	1.0	1.7	2.8	6.5	23.3	3.1	151.1	20.8
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	7427	0.7	1.1	1.7	2.6	4.8	12.6	2.5	197.7	22.3

2022 selenium in PM_2.5 annual statistics

Unit: nanograms per cubic metre (ng/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
29000	Hamilton Downtown	Elgin St./Kelly St.	4714	0.02	0.11	0.24	0.54	1.84	6.00	0.68	13.57	4.35
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	7427	0.06	0.15	0.25	0.41	0.99	5.82	0.56	61.62	10.46

2022 zinc in PM_2.5 annual statistics

Unit: nanograms per cubic metre (ng/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
29000	Hamilton Downtown	Elgin St./Kelly St.	4714	1.6	4.0	7.4	13.1	36.9	272.9	21.0	1,031.0	173.4
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	7427	4.2	7.6	11.4	17.2	33.8	111.1	18.4	3,637.9	347.5

2022 organics in PM_2.5 annual statistics

Unit: micrograms per cubic metre (µg/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	8101	1.3	2.3	3.4	5.2	9.0	16.0	4.42	79.3	17.31

2022 sulphate in PM_2.5 annual statistics

Unit: micrograms per cubic metre (µg/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	8101	0.1	0.3	0.5	0.7	1.4	2.8	0.65	9.4	3.63

2022 nitrate in PM_2.5 annual statistics

Unit: micrograms per cubic metre (µg/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	8101	0.1	0.2	0.3	0.7	2.2	5.6	0.77	9.5	6.77

2022 ammonium in PM_2.5 annual statistics

Unit: micrograms per cubic metre (µg/m³)

ID	City	Location	Valid h	10%	30%	50%	70%	90%	99%	Mean	Maximum 1h	Maximum 24h
83126	Toronto Hwy 401	Hwy 401 at 125 Resources Rd.	8101	0.0	0.2	0.3	0.4	1.0	2.4	0.42	32.0	2.67

7-year trend NO₂

Annual mean (ppb)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 year (%)
12008	Windsor Downtown	11.40	11.10	10.99	10.94	8.99	9.56	9.37	-20.3
12016	Windsor West	10.60	9.90	8.77	9.98	8.14	8.44	7.98	-23.5
29000	Hamilton Downtown	11.90	11.90	11.63	12.49	9.87	10.23	10.61	-17.9
29214	Hamilton Mountain	7.90	7.80	7.76	8.81	6.91	6.33	6.09	-26.4
33003	Toronto East	12.10	11.50	10.55	10.24	8.41	9.50	9.93	-23.3
34021	Toronto North	12.00	10.50	10.35	10.51	8.89	9.30	10.21	-15.2
35033	Etobicoke South	14.69	15.47	14.75	14.74	12.24	13.85	13.68	-12.5
35125	Toronto West	15.70	15.00	14.41	14.62	12.10	12.88	13.21	-16.7
63203	Thunder Bay	7.10	6.70	7.48	6.65	6.11	6.53	6.98	-8.5
75010	North Bay	4.70	4.60	4.93	5.11	4.26	3.92	4.12	-14.0
83126	Toronto Hwy 401	18.95	18.83	18.63	18.55	16.09	17.64	17.78	-9.9
83133	Toronto Island	6.37	INS	5.86	6.35	5.12	6.54	6.64	N-SSS

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend PM_2.5

Annual mean (µg/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 year (%)
12008	Windsor Downtown	8.10	7.80	8.48	7.79	7.05	8.34	7.83	N-SSS
12016	Windsor West	8.50	8.50	8.66	9.05	8.77	9.57	8.82	9.3
29000	Hamilton Downtown	8.20	8.50	9.18	8.83	8.08	8.89	8.64	N-SSS
29214	Hamilton Mountain	7.20	7.40	7.73	7.87	7.06	8.02	7.71	N-SSS
33003	Toronto East	7.00	7.40	7.18	6.99	6.65	7.41	6.70	N-SSS
34021	Toronto North	7.30	7.40	7.60	6.84	6.41	7.37	6.79	N-SSS
35033	Etobicoke South	8.06	8.17	8.21	7.81	7.38	8.53	7.73	N-SSS
35125	Toronto West	7.00	7.40	7.71	7.18	6.88	7.66	6.90	N-SSS
63203	Thunder Bay	4.90	5.10	5.95	5.10	5.45	6.61	5.03	N-SSS
75010	North Bay	4.60	4.60	5.49	4.49	4.57	5.66	5.06	12.2
83126	Toronto Hwy 401	9.21	9.39	9.01	8.72	8.76	9.34	9.09	N-SSS
83133	Toronto Island	6.84	6.48	7.08	6.49	6.11	6.81	5.79	-1.4

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for ultrafine particles

Annual mean (#/cm³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
34021	Toronto North	11953	12074	12293	10873	9056	10262	10697	-18.0
83126	Toronto Hwy 401	43280	39053	37984	39831	40635	42579	40806	N-SSS
83133	Toronto Island	INS	INS	INS	6693	6126	6415	7555	N-SSS

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for black carbon

Annual mean (µg/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
12008	Windsor Downtown	0.53	0.50	0.57	0.59	0.43	0.49	0.40	-23.4
12016	Windsor West	0.70	0.65	0.60	0.59	0.45	0.50	0.44	-40.9
29000	Hamilton Downtown	0.51	0.71	0.72	0.67	0.57	0.57	0.51	N-SSS
33003	Toronto East	0.62	0.62	0.45	0.45	0.45	0.44	0.39	-40.5
34021	Toronto North	0.62	0.60	0.49	0.53	0.51	0.47	0.42	-27.1
35033	Etobicoke South	0.89	0.97	0.79	0.83	0.88	0.69	0.61	-26.7
83126	Toronto Hwy 401	1.62	1.51	1.31	1.43	1.20	1.18	1.05	-31.8
83133	Toronto Island	0.44	0.35	0.37	0.37	0.34	0.33	0.29	-32.4

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for iron in PM_2.5

Annual mean (ng/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
29000	Hamilton Downtown	116.6	116.9	105.9	106.9	88.3	104.0	108.6	-23.3
83126	Toronto Hwy 401	INS	261.6	275.7	INS	288.6	257.0	280.8	N-SSS

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for copper in PM_2.5

Annual mean (ng/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
29000	Hamilton Downtown	4.7	4.8	4.2	4.0	3.5	4.4	4.5	N-SSS
83126	Toronto Hwy 401	INS	11.5	11.9	INS	10.2	9.8	8.5	-30.1

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for manganese in PM_2.5

Annual mean (ng/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 6 years (%)
29000	Hamilton Downtown	5.5	3.9	3.5	4.2	2.9	3.4	3.5	-51.7
83126	Toronto Hwy 401	INS	3.7	3.7	INS	3.7	3.6	3.8	N-SSS

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for lead in PM_2.5

Annual mean (ng/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
29000	Hamilton Downtown	3.5	3.6	3.6	3.6	3.3	3.5	3.1	N-SSS
83126	Toronto Hwy 401	INS	3.5	3.2	INS	2.8	2.9	2.5	-20.0

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for selenium in PM_2.5

Annual mean (ng/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
29000	Hamilton Downtown	0.61	0.59	0.67	0.62	0.58	0.68	0.68	N-SSS
83126	Toronto Hwy 401	INS	0.45	0.43	INS	0.59	0.66	0.56	30.7

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.
N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for zinc in PM_2.5

Annual mean (ng/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
29000	Hamilton Downtown	40.1	25.8	26.5	29.0	20.5	23.9	21.0	-45.4
83126	Toronto Hwy 401	INS	24.2	22.3	INS	18.1	19.5	18.4	-27.8

Notes:

INS indicates there was insufficient data to calculate a valid annual mean.

7-year trend for organics in PM_2.5

Annual mean (µg/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
83126	Toronto Hwy 401	4.13	7.01	5.20	3.88	4.83	3.94	4.42	N-SSS

Notes:

N-SSS - Non-Significant Sen's Slope (significant trend not detected).

7-year trend for sulphate in PM_2.5

Annual mean (µg/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
83126	Toronto Hwy 401	0.91	1.12	0.66	0.65	0.67	0.56	0.65	-34.4

7-year trend for nitrate in PM_2.5

Annual mean (µg/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
83126	Toronto Hwy 401	1.31	1.71	1.65	1.20	1.38	1.14	0.77	-36.2

7-year trend for ammonium in PM_2.5

Annual mean (µg/m³)

ID	City/Town	2016	2017	2018	2019	2020	2021	2022	Change over 7 years (%)
83126	Toronto Hwy 401	0.73	1.46	0.65	0.41	1.06	0.89	0.42	-26.9

Updated: November 08, 2024

Published: November 08, 2024

Appendix

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Monitoring network operations

Network description

Quality assurance and quality control

Data base

Network descriptive table

Annual statistics and trends

Other informative tables

2022 air monitoring network

Notes:

2022 annual statistics

2022 nitric oxide (NO) annual statistics

2022 nitrogen dioxide (NO2) annual statistics

2022 nitrogen oxides (NOx) annual statistics

2022 fine particulate matter (PM2.5) annual statistics

Notes

2022 ground-level ozone (O3) annual statistics

2022 sulphur dioxide (SO2) annual statistics

2022 carbon monoxide (CO) annual statistics

2022 total reduced sulphur (TRS) compounds annual statistics

2022 benzene annual statistics

2022 toluene annual statistics

2022 ethylbenzene annual statistics

2022 m- and p-xylene annual statistics

2022 o-xylene annual statistics

2022 1,3-butadiene annual statistics

10-year trends

10-year trend for nitric oxide (NO)

Notes:

10-year trend for nitrogen dioxide (NO2)

Notes:

10-year trend for nitrogen oxides (NOx)

Notes:

10-year trend for fine particulate matter (PM2.5)

Notes:

10-year trend for ground-level ozone (O3) 1h maximum

Notes:

10-year trend for ground-level ozone (O3)

Notes:

10-year trend for ground-level ozone (O3) summer means (May - September)

Notes:

10-year trend for ground-level ozone (O3) winter means (January-April, October-December)

Notes:

10-year trend for sulphur dioxide (SO2)

Notes:

10-year trend for carbon monoxide (CO)

Note:

10-year trend for benzene

Notes:

10-year trend for toluene

Notes:

10-year trend for ethylbenzene

Notes:

10-year trend for m- and p-xylene

Notes:

10-year trend for o-xylene

Notes:

10-year trend for 1,3-butadiene

Notes:

Canadian Ambient Air Quality Standard reporting

Note:

Note:

Notes:

Notes:

Management levels for CAAQS pollutants

Air quality management actions by air zone area

Ontario air quality management actions by air zone

Northern Ontario (excluding Sault Ste. Marie and Sudbury)

CAAQS management levels

Southern Ontario (excluding Sarnia/St. Clair Township and Hamilton)

CAAQS management levels

Sudbury

CAAQS management levels

Sault Ste. Marie

CAAQS management levels

Sarnia/St. Clair Township

CAAQS management levels

Hamilton

CAAQS management levels

2022 nitrogen dioxide (NO₂) annual statistics

2022 nitrogen oxides (NO_x) annual statistics

2022 fine particulate matter (PM_2.5) annual statistics

2022 ground-level ozone (O₃) annual statistics

2022 sulphur dioxide (SO₂) annual statistics

10-year trend for nitrogen dioxide (NO₂)

10-year trend for nitrogen oxides (NO_x)

10-year trend for fine particulate matter (PM_2.5)

10-year trend for ground-level ozone (O₃) 1h maximum

10-year trend for ground-level ozone (O₃)

10-year trend for ground-level ozone (O₃) summer means (May - September)

10-year trend for ground-level ozone (O₃) winter means (January-April, October-December)

10-year trend for sulphur dioxide (SO₂)

2022 nitrogen dioxide (NO₂) annual statistics

2022 fine particulate matter (PM_2.5) annual statistics

2022 iron in PM_2.5 annual statistics

2022 copper in PM_2.5 annual statistics

2022 manganese in PM_2.5 annual statistics

2022 lead in PM_2.5 annual statistics

2022 selenium in PM_2.5 annual statistics

2022 zinc in PM_2.5 annual statistics

2022 organics in PM_2.5 annual statistics

2022 sulphate in PM_2.5 annual statistics

2022 nitrate in PM_2.5 annual statistics

2022 ammonium in PM_2.5 annual statistics

7-year trend NO₂

7-year trend PM_2.5

7-year trend for iron in PM_2.5

7-year trend for copper in PM_2.5

7-year trend for manganese in PM_2.5

7-year trend for lead in PM_2.5

7-year trend for selenium in PM_2.5

7-year trend for zinc in PM_2.5

7-year trend for organics in PM_2.5

7-year trend for sulphate in PM_2.5

7-year trend for nitrate in PM_2.5

7-year trend for ammonium in PM_2.5